I'm trying to add a video player to an elderly TV. I have OSMC working well with HDMI, but I struggled to get it to work on Composite output. It's Raspberry Pi 3 B+ v1.2. Having been through the numerous posts, suggesting modifications to the config.txt, I decided that the audio buzz I could hear on the right channel was more than just noise, and swapped the Audio Right for the Video. Hey presto. Clear sound and Picture. I have subsequently tried several 3.5mm / RCA leads. If swap red / yellow, they all work. One of them even has the yellow labelled as "Comp Vid", but it only works if I connect the "Audio R" intot he video.
So, the question is: is the Raspberry Pi atypical or unusual? Is it simply that there is no particular standard and coincidence that my three cables are all the same (inappropriate) configuration?