Having ruled out the cable (tried 3 different ones), the PSU (3 different ones aswel) and the TV (3 different ones aswel), would it be reasonable to assume i have a faulty raspberry pi?
With four wires there are potentially 24 different wiring schemes possible, of which only one will be 100% correct.
So no, unless you can actually measure the cable and confirm the connections are correct you should expect that all three the cables you are using are wired incorrectly!
Most importantly the GND signal (connected to the outer shells of all the RCA connectors) should be connected to the the "ring" nearest to the sleeve of the four pole connector. Without the correct GND wiring no correct video or audio output is possible, but WITH the GND wiring correct its possible to simply switch around the RCA connectors to correct for any wiring differences.
The PI actually uses one of the most often used wiring schemes, as used by Ipods and zunes, but its completely possible that if you have a dozen random four pole to RCA adapters (or cables) none of them will use the "iPod" standard!
If you look at the picture av-pinouts.jpg, you will notice that three of the four described wiring schemes have at least GND on Pin 2, which makes them at least usable, but all the cables that use from one of these "Archos, gigabit, creative Zen, Vision Series, Crown iAudio, and apple iBook" have the wiring scheme that puts GND on Pin 1 instead of Pin 2!, and for the video signal that means that the signal received will have Video and GND reversed, so the signal will actually be inversed (negative).
That's the bad news, the good news that cables using any of the other wiring schemes are either (nearly) perfect, or at least usable! The only difference between an original iPod cable and a PI seems to be that left and right audio channels are interchanged, perhaps this can be solved with software (which detects Composite video is used then exchanges the audio channels), but you can also simply swap the red and white RCA plugs if you care about that.
As for a standard camcorder cable, that can be used too simply by exchanging the right and video RCA connectors, that is the yellow and the red one!
Actually the PI's wiring scheme makes more sense than the iPod ones, as when you ignore the video signal you can simply plug in a three pins (TRS) plug for audio, and GND left and right signal will be correct. The PI correctly uses the
tip for the left audio signal, not the right audio signal ( a memory help is that "Right" and "Ring" both start with the same letters). The fact that the video signal will be shorted to GND is of no concern as the designers have taken measures to make that possible without any problem.
none of the video modes work. as they should. I have a pal tv, and am currently running a pal signal into it (tvservice -s confirms it)
