ah well at least its not just radio related /areial.(which would have possibly been an easier fix ?)
sounds like the unit will have to be removed one way or the other .connections are worth checking obviously but cannot see that any bad connection on the back would allow the unit to still work but cut all 4 output channels.
unless anyone knows exactly where to look inside specifically it sounds like a bad internal solder joint or connection somewhere. i had a similar issue earlier this year with a different unit where everything was crisp and clear except the cassette output which was distorted. that took a lot of head scratching to sort. lots of joints were resoldered and various components swapped untill it was resolved.
one more silly question thou sorry probably not the fault but ....does your car have anything that splices into and cuts the audio for any reason such as a phone system or similar ? wasnt some models fitted with a trafficmaster system ? how does that connect in ? ?
Yes, I'm in agreement with your diagnosis. Think it likely that it is a faulty joint inside the unit. I've ordered a new set of removal pins, specifically for the CDR 2005, so hopefully I'll be able to remove it. Frankly, I'm useless at soldering, so looking to get a secondhand unit or, conceivably, a new touch-screen unit.
In answer to your second question, no i don't have anything that splices into the audio.