Display fades to white/black and freezes

[ge0x58]

Hi,
We’re using the official 7″ Touchscreen Monitor together with a raspberry pi 2. Sometimes the display fades to white/black and freezes (the pi is still responsive). A power cycle is required to recover from this state, reboot does not normally work.

The pi fails to detect the display and defaults to NTSC video mode.
During normal operation:

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tvservice -s 
state 0x400000 [LCD], 800x480 @ 60.00Hz, progressive
dmesg | grep rpi-ft5406
[    3.553003] rpi-ft5406 rpi_ft5406: Probing device

After failure :

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tvservice -s 
state 0x40001 [NTSC 4:3], 720x480 @ 60.00Hz, interlaced.  
dmesg | grep rpi-ft5406
(returns nothing)

There seems to be a lock up on I2C0. There is activity on SCK0 during reboot but SDA0 is held constantly low. A reset would probably cause the rpi to release the bus? In that case the culprit seems to be the MCU on the display board.

Is there any way to recover from this state except power cycle?
I will try to reduce the I2C0 clock rate. Any other suggestions?

I have followed the troubleshooting guide @ https://www.raspberrypi.org/documentati ... hooting.md:

• Reseated all cables.
• Checked power supply. No glitch outside 4.75 – 5.25 V detected with oscilloscope. No rainbow square.

--- Setup ---
Hardware:
Raspberry Pi 2 Model B V1.1
Raspberry Pi Display V1.1

OS:
RASPBIAN JESSIE Full desktop image based on Debian Jessie
Version:May 2016
Release date:2016-05-27
Kernel version:4.4
OS upgraded according to instruction @ https://thepihut.com/blogs/raspberry-pi ... mbly-guide:

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sudo apt-get update
sudo apt-get upgrade
sudo apt-get dist-upgrade 
sudo apt-get install raspberrypi-ui-mods 
sudo apt-get install raspberrypi-net-mods

uname -a
Linux raspberrypi 4.4.13-v7+ #894 SMP Mon Jun 13 13:13:27 BST 2016 armv7l GNU/Linux

Power supply:
Separate bench PSU @ 5V, 3A for rpi and display, shared ground.

Thank you for your time!
/ge0x58