1uke_ wrote: ↑
Fri Oct 25, 2019 9:25 pm
I am using a Raspberry Pi 2b+ running Raspbian Stretch.
Presumably you mean a "Pi 2 Model B Version 1.2" which uses a BCM2837 ( perhaps even a BCM2837B these days ) rather than the BCM2836 fitted to the original 2B boards.
I also tend to think of that as a "2B+" to discriminate between the two but that is not its official designation.
There is no reason I can see why composite wouldn't work with any 2B and would also suspect the problem being an incorrectly wired connector cable.
About a third of the 3.5mm jack to video cables I have are directly compatible with the Pi wiring scheme, the others not. As suggested, you can use a resistance meter as a continuity checker to figure out how what you have is wired.