onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 4:37 pm

Hello all,

I unboxed my first Raspberry Pi 4 8gb last night and was surprised to find that it would not output HDMI to any of the three monitors or one HDMI TV I tried it with.

I was even *more* surprised to find, after a bit of Googling, that this seems to be a very, very common issue with 4s.

This is perhaps my 10th Raspi and never have I had such a recalcitrant issue. None of the numerous "all you have to do is..." posts, troubleshooting suggests, config.txt tweaks, etc., have resolved this problem. I have flashed a new OS. I can access the Pi by SSH, so I know the board is working and can boot. I seem to be in the same position as many others who are stuck with a semi-functional board out-of-the-box.

Are there any additional troubleshooting steps not outlined in the sticky posts here? Is this a product design issue (e.g., pushing the hardware too far with dual HDMI)? I totally understand how much hacking and tweaking is to be expected with this kind of product, but something doesn't seem right here in terms of basic compatibility.

Very eager to try any other alternatives available before returning this board as I had great plans for the 8gb of RAM on this brand new board.

onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 4:42 pm

Further to this, I have reviewed the following:

viewtopic.php?f=28&t=5851

viewtopic.php?f=28&t=58151

And implemented as many potentially relevant fixes as I can, without success. I see plenty of other posts here and around the web that suggest unresolved issues of this nature, too. I'm hoping that someone who may have faced and fixed this problem by some novel means might be able to assist.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 4:43 pm

Odd its not working on so many. We have had reports of some monitors/TV's not working, but we've never replicated it in house. And remember, we have sold over 2 MILLION Pi4's so if it was common we would be inundated with issues.

The HDMI blocks were changed on the Pi4, effectively there are now two of them that now run at up to 4kp60, so it's not a 'overstressing the HW' issue, or a HW design issue. The only known problem is with a very specific resolution 1366x768 which is the only standard resolution that has odd numbers in its timing - that breaks as the new HDMI blocks run at 2 pixels per clock, so need even timings.

I'd be inclined to think that the Pi4 was faulty in some way, OR that the cable you are using is not working.

What resolutions/makes are the monitors that do not work?
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 4:44 pm

One further point - I have ordered two additional micro HDMI cables to eliminate the possibility that my cable is to blame for the problem.

timg236
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 690
Joined: Thu Jun 21, 2018 4:30 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 4:56 pm

It's would be extremely unusual (almost unheard of) for both HDMI ports to be broken so badly that I2C and hotplug doesn't work on either port given that the analog signals are tested on both ports on every board at the factory.

To debug, create a clean Raspberry Pi OS image with the Raspberry Pi Imager. Unplug all USB devices, add hdmi_safe=1 to config.txt and connect the HDMI cable directly to the display.

https://www.raspberrypi.org/documentati ... t/video.md

onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 4:59 pm

I'd be inclined to think that the Pi4 was faulty in some way, OR that the cable you are using is not working.

What resolutions/makes are the monitors that do not work?
Yes, I want to eliminate the cable as a factor as well. This is a relatively unusual connector so I only have one cable on-hand. I had this cable for use with an Asus convertible tablet, but had rarely if ever taken it out of storage until yesterday so I have little reason to believe it could be damaged but also little track record, either. The two cables I have on order are from a Pi-specific vendor, so that should help.

So far I have tried:
  • TCL 50S425-CA 4K TV
  • BENQ 27" monitor (1920x1080 native resolution)
  • ASUS 24" monitor (1920x1080 native resolution)
  • DELL E228WFP 22" monitor - via HDMI-to-DVI adaptor (1680 x 1050 native resolution)
Last edited by onshi on Fri Jun 05, 2020 5:02 pm, edited 1 time in total.

onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 5:01 pm

timg236 wrote:
Fri Jun 05, 2020 4:56 pm
To debug, create a clean Raspberry Pi OS image with the Raspberry Pi Imager. Unplug all USB devices, add hdmi_safe=1 to config.txt and connect the HDMI cable directly to the display.

https://www.raspberrypi.org/documentati ... t/video.md

This is the procedure I alluded to in my original post. It did not work. I will try again when I have an alternate HDMI cable.

timg236
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 690
Joined: Thu Jun 21, 2018 4:30 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 5:03 pm

onshi wrote:
Fri Jun 05, 2020 5:01 pm
timg236 wrote:
Fri Jun 05, 2020 4:56 pm
To debug, create a clean Raspberry Pi OS image with the Raspberry Pi Imager. Unplug all USB devices, add hdmi_safe=1 to config.txt and connect the HDMI cable directly to the display.

https://www.raspberrypi.org/documentati ... t/video.md

This is the procedure I alluded to in my original post. It did not work. I will try again when I have an alternate HDMI cable.
Thanks, you could you also try running tvservice -d to see if the Pi can read the EDID from the display.

iwestbury
Posts: 2
Joined: Fri Jun 05, 2020 5:15 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 5:27 pm

I have the 1366 x 768 resolution. I am using NOOBS so I get the option to edit config on boot up and have managed to get an acceptable (though not perfect) display by changing the HDMI group and mode settings and then messing with the display resolution options. The odd thing is that when NOOBS first loads it appears to be fine so I'm assuming that NOOBS must load the display settings differently? It only fails when I update the software.

My question is whether the 1366 x 768 resolution issue will be resolved in the future.

Thanks otherwise, it's now my go to desktop!

User avatar
HawaiianPi
Posts: 6001
Joined: Mon Apr 08, 2013 4:53 am
Location: Aloha, Oregon USA

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 5:33 pm

I didn't have any trouble with either of my Pi 4B computers and my HP Pavilion 27xw monitor. They just worked with some old micro-HDMI cables and adapters I had left-over from an Ultrabook I gave to my niece. I have also used them with a few other monitors, and they just worked as well.

I do see others having trouble, but often their problems are resolved after some troubleshooting.

We are dealing with a new GPU and graphics drivers, so some teething problems are to be expected. Adapters are always a source of trouble as well, even with older model Pi computers (so it's best to use a direct micro-HDMI to HDMI cable, if you can, but I have used adapters with mine and they worked for me).

Not really sure why some people have trouble while most others don't, but the Pi 4B works fine for me. ¯\_(ツ)_/¯

Most common issues I've seen are:
  • Not having the correct input selected on the display.
  • Using the HDMI-1 port with a single display (try HDMI-0, the one closest to the USB-C power port).
  • Bad adapter or cable.
  • Inability to read, or bad EDID info from the display (the Pi4 seems to be more sensitive to this than older models).
  • Bad or inadequate power supply (using the HDMI ports requires additional power).
  • Using a case that doesn't allow the cables to be fully inserted.
  • HDMI adapter that doesn't pass the ground connection through.
My mind is like a browser. 27 tabs are open, 9 aren't responding,
lots of pop-ups...and where is that annoying music coming from?

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 6:19 pm

iwestbury wrote:
Fri Jun 05, 2020 5:27 pm
I have the 1366 x 768 resolution. I am using NOOBS so I get the option to edit config on boot up and have managed to get an acceptable (though not perfect) display by changing the HDMI group and mode settings and then messing with the display resolution options. The odd thing is that when NOOBS first loads it appears to be fine so I'm assuming that NOOBS must load the display settings differently? It only fails when I update the software.

My question is whether the 1366 x 768 resolution issue will be resolved in the future.

Thanks otherwise, it's now my go to desktop!
The 2 pixels per clock thing is in the HW, so there nothing can be done there. We are currently waiting for Broadcom to get back to us on some questions we had about it - There are two bit of HW involved, and we reckon that we should be able to compensate for one having problems with the odd timings with the other one - but our changes didn't work, contrary to the docs. We may just have to hack the timings a bit to make them even and hope it works for the majority of affected displays. We now have a monitor that is affected (previously we could not buy on in the UK - they are a pretty old design), so at least can test.

Meanwhile, best to keep this thread clear of side track issues like this.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 05, 2020 10:24 pm

HawaiianPi wrote:
Fri Jun 05, 2020 5:33 pm
  • Bad or inadequate power supply (using the HDMI ports requires additional power).
  • Using a case that doesn't allow the cables to be fully inserted.
  • HDMI adapter that doesn't pass the ground connection through.
I'm using the black/grey "official case" and a pretty robust-looking 3A USB-C power supply that came with my Pi. The HDMI cable I'm using seems to seat fully into the socket while the board is in the case, but to test this theory I did try removing it from the case while testing with my TV last night. That did not resolve the issue. I will try it out of the case if the new cable doesn't help.

vaughannt
Posts: 1
Joined: Sun Jun 07, 2020 7:28 pm

Re: How common are HDMI issues for RasPi 4?

Sun Jun 07, 2020 7:49 pm

I am having the same issue with my TV that is 1366x728 and rpi 4/4GB. I have tried many configurations and nothing seems to work... Doesn't help that I am a complete noob to all of this, but there are dozens of posts out there with my same problem.

onshi
Posts: 7
Joined: Fri Jun 05, 2020 4:24 pm

Re: How common are HDMI issues for RasPi 4?

Sun Jun 07, 2020 8:19 pm

Eager to resolve this, I had a pair of micro HDMI-to-HDMI adapters shipped quickly by Amazon.

Result: success! And the video is beautiful.So, clearly the problem must have been with my original micro HDMI cable, even though it still works with my Asus tablet (itself the only other micro HDMI device I have on hand).

Are there any known/suspected pins on these cables that could be to blame? I'd be happy to test it with a multimeter before I toss it to avoid any future angst.

boplucas
Posts: 1
Joined: Thu Jun 11, 2020 4:41 am

Re: How common are HDMI issues for RasPi 4?

Thu Jun 11, 2020 6:12 am

I just went through three pi4s trying to resolve this issue! I have a 3b+ and 0w that work with a Samsung monitor, so when my first pi4 didn't work, I had it replaced. When the second one also didn't work, I tried a second TV and different HDMI cables, but it also didn't work - so I assumed I lucked into a "bad batch" and returned it for a refund. Then they announced the 8GB version, so I purchased that from a completely different company. Also, it included an SD card with Noobs pre-etched, so it had to work out-of-the-box. But it didn't work! But that should be impossible that I got that many "duds", so I found a 3rd HDMI TV, and this time it worked. Just to make sure, I continued testing - trying different cables and retrying the TVs that didn't work. I consistently found that all Pi's worked with all cables and adapters, so those weren't an issue. But, the pi4 only worked with the one TV, while the 3b+ and 0w works on all three. I'm not sure what's magical about that one TV - it's the oldest of the three - but it works without having to change anything on the pi or do anything manually on the TV, other than selecting the proper port.

I'd love to know why, but at least I was able to configure SSH, so for now, I don't need my other two TVs to work. But there is definitely something different about how the pi4 outputs HDMI than the other two.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Thu Jun 11, 2020 11:38 am

boplucas wrote:
Thu Jun 11, 2020 6:12 am
I'd love to know why, but at least I was able to configure SSH, so for now, I don't need my other two TVs to work. But there is definitely something different about how the pi4 outputs HDMI than the other two.
The Pi4 has a different HDMI HW block, so it can support 4k. There are also differences if you are using legacy vs KMS drivers. Legacy was the default on the Pi3, FKMS is the default on the Pi4.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

RichardS
Posts: 33
Joined: Sat Mar 25, 2017 2:40 am

Re: How common are HDMI issues for RasPi 4?

Fri Jun 12, 2020 9:10 pm

boplucas wrote:
Thu Jun 11, 2020 6:12 am
I'd love to know why, but at least I was able to configure SSH, so for now, I don't need my other two TVs to work. But there is definitely something different about how the pi4 outputs HDMI than the other two.
Use the monitor that does work, and bring up a terminal and type

sudo raspi-config

Then go to the Advanced settings and select the "Legacy" GPU video driver and see if that improves HDMI compatibility for your equipment.
jamesh wrote:
Thu Jun 11, 2020 11:38 am
The Pi4 has a different HDMI HW block, so it can support 4k. There are also differences if you are using legacy vs KMS drivers. Legacy was the default on the Pi3, FKMS is the default on the Pi4.
James, for those that can't get even one monitor to work (and therefor can't use the above raspi-config fix) - as the developer, perhaps you could explain how to easily switch back to the Legacy Video driver by editing the configuration files manually ???

Also you may want to give some thought to temporarily going back to the Legacy Driver as the Default because ...

THE LEGACY DRIVER ALSO FIXES THE NO BACKLIGHT SHUTOFF DURING BLANKING ISSUE THAT MANY FOLKS ARE COMPLAINING ABOUT ON OLDER HDMI MONITORS AND TELEVISIONS.

This would give you some breathing room until you "get around" to fixing the newer OpenGL driver so that blanking also works properly. ;)

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Fri Jun 12, 2020 9:42 pm

RichardS wrote:
Fri Jun 12, 2020 9:10 pm
boplucas wrote:
Thu Jun 11, 2020 6:12 am
I'd love to know why, but at least I was able to configure SSH, so for now, I don't need my other two TVs to work. But there is definitely something different about how the pi4 outputs HDMI than the other two.
Use the monitor that does work, and bring up a terminal and type

sudo raspi-config

Then go to the Advanced settings and select the "Legacy" GPU video driver and see if that improves HDMI compatibility for your equipment.
jamesh wrote:
Thu Jun 11, 2020 11:38 am
The Pi4 has a different HDMI HW block, so it can support 4k. There are also differences if you are using legacy vs KMS drivers. Legacy was the default on the Pi3, FKMS is the default on the Pi4.
James, for those that can't get even one monitor to work (and therefor can't use the above raspi-config fix) - as the developer, perhaps you could explain how to easily switch back to the Legacy Video driver by editing the configuration files manually ???

Also you may want to give some thought to temporarily going back to the Legacy Driver as the Default because ...

THE LEGACY DRIVER ALSO FIXES THE NO BACKLIGHT SHUTOFF DURING BLANKING ISSUE THAT MANY FOLKS ARE COMPLAINING ABOUT ON OLDER HDMI MONITORS AND TELEVISIONS.

This would give you some breathing room until you "get around" to fixing the newer OpenGL driver so that blanking also works properly. ;)
Turning off the legacy driver turns off all 3D acceleration, which slows the desktop down significantly. The Pi4 cannot use the legacy 3D.

Hence you only turn if off if you really REALLY need to, and we definitely cannot have it as a default.

Turning off FKMS is as simple as editing the config.txt file and commenting out the line with FKMS in it.

You are the only person I know who has a problem with the blanking. Which AFAICR is pretty similar functionally to that in the legacy driver anyway.

There is clearly an issue with some devices and the new driver (which BTW is now a standard Linux DRM driver rather than the custom one we had before), and/or the HW block itself. We are talking to Broadcom about it.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

RichardS
Posts: 33
Joined: Sat Mar 25, 2017 2:40 am

Re: How common are HDMI issues for RasPi 4?

Sat Jun 13, 2020 12:12 am

jamesh wrote:
Fri Jun 12, 2020 9:42 pm
RichardS wrote:
Fri Jun 12, 2020 9:10 pm

THE LEGACY DRIVER ALSO FIXES THE NO BACKLIGHT SHUTOFF DURING BLANKING ISSUE THAT MANY FOLKS ARE COMPLAINING ABOUT ON OLDER HDMI MONITORS AND TELEVISIONS.
Turning off the legacy driver turns off all 3D acceleration, which slows the desktop down significantly. The Pi4 cannot use the legacy 3D.

Hence you only turn if off if you really REALLY need to, and we definitely cannot have it as a default.

Turning off FKMS is as simple as editing the config.txt file and commenting out the line with FKMS in it.

You are the only person I know who has a problem with the blanking. Which AFAICR is pretty similar functionally to that in the legacy driver anyway.

There is clearly an issue with some devices and the new driver (which BTW is now a standard Linux DRM driver rather than the custom one we had before), and/or the HW block itself. We are talking to Broadcom about it.
Thanks for the info on manually disabling the FKMS driver. So far as the impact of disabling the driver goes - I am a BIG fan of the Pi Foundations efforts to bring the Pi up to full Linux OpenGL and Vulkan compatibility (like competing SBCs like the Jetson Nano) but, based on my early testing the 3D was just not working well enough to even bother with, so I disabled the FKMS driver.

The Jetson Nano has full OpenGL 4.5 tested and manufacture certified as standard compliant, and literally TEN TIMES the GPU performance of the Pi, so that will remain my goto SBC for OpenGL/GLES for now - but the Pi 4 actually outperforms the Nano on raw CPU and general Desktop performance and responsiveness, even with the non-FKMS Legacy Driver and I absolutely LOVE the Pi 4 as a mini desktop to turn dumb-TV's into Smart-Tv's -- but in that application proper backlight control is essential.

As to me being the only person effected by the bad blanking bug, you apparently failed to notice THIS, and THIS, and THIS, and THIS, and THIS, and THIS, and THIS, and THIS post in the thread I created where someone else was begging me to tell him how I DID get my Pi 4 to blank properly - you killed the thread before I could respond and tell him that I had troubleshot the problem a little more and found that my new 8GB Pi 4 would ALSO blank properly after simply switching to the Legacy Video Driver.

3D works well enough for stuff like Retropi but that is a custom image anyway, and I'm guessing that most folks won't miss the 3D much on the Desktop for now, and my personal experience switching back to the Legacy Driver was that it was solid and stable enough that my 4 GB Pi 4 accumulated more than 60 Days uptime turning my Dumb-TV into a Smart-TV without a crash while providing occasional YouTube viewing and light web surfing which is pretty impressive.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Sat Jun 13, 2020 7:12 am

You misunderstand. Turning off 3d doesn't just stop 3d working it also slows down the desktop as it it used for much faster rendering of Windows, the 3d is the graphics backend for the desktop itself.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

Schorschi
Posts: 245
Joined: Thu Nov 22, 2012 9:38 pm

Re: How common are HDMI issues for RasPi 4?

Wed Jun 17, 2020 3:06 pm

For what it is worth, i have 3 Pi4 devices and they all refuse to see HDMI monitor on boot up randomly presenting the monitor image, when it rarely appears. I have tried TVs, Dell monitors, etc. The issue is core to the Pi4, not a specific monitor or TV from my experience. I have tried enabling the various options in config.txt, nothing seems to fix the problem consistently. Every other Pi model I have, which is many, all work fine with the same monitors and TVs, it is ONLY the Pi4 devices that act up.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Wed Jun 17, 2020 4:50 pm

Schorschi wrote:
Wed Jun 17, 2020 3:06 pm
For what it is worth, i have 3 Pi4 devices and they all refuse to see HDMI monitor on boot up randomly presenting the monitor image, when it rarely appears. I have tried TVs, Dell monitors, etc. The issue is core to the Pi4, not a specific monitor or TV from my experience. I have tried enabling the various options in config.txt, nothing seems to fix the problem consistently. Every other Pi model I have, which is many, all work fine with the same monitors and TVs, it is ONLY the Pi4 devices that act up.
This is really weird. We have NO failures at all on our office monitors and yet some people hardly get theirs working at all. Your case sounds like a defective socket, but to get that on multiple devices would be extremely strange. Sometimes you might get the odd failure, but not three from three. I presume you have also tried multiple cables?
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

cycnus
Posts: 1
Joined: Sun Nov 22, 2020 10:34 am

Re: How common are HDMI issues for RasPi 4?

Sun Nov 22, 2020 10:47 am

Hello. I have the same trouble. Soooo difficult to get something displayed on my Samsung 4K TV. I never had trouble with other electronic devices using the same cables I use with the Pi 4 (4 Gb). TYhere is really a piece of harware or software that need to be corrected. I really ask mysleft what I can do with my defective Pi 4. First time I buy a Pi, last time I think. I should have bought a mini PC. Hoping you will correct the problem with a solution.

jamesh
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 27436
Joined: Sat Jul 30, 2011 7:41 pm

Re: How common are HDMI issues for RasPi 4?

Sun Nov 22, 2020 1:52 pm

We are not aware of any HW defects in the Pi4, except for one issue with specifically 1366x768 devices, which a 4k TV clearly isn't.

So what symptoms are you seeing? I've used the Pi400 (same HDMI as the Pi4) on a Samsung TV with no problems. I'll try it on the 4k TV I have up stairs tomorrow to see if I can replicate this.
Principal Software Engineer at Raspberry Pi (Trading) Ltd.
Contrary to popular belief, humorous signatures are allowed.
I've been saying "Mucho" to my Spanish friend a lot more lately. It means a lot to him.

Return to “Troubleshooting”