radio intereference

Hi, First of all, i'd like to apologize and thank all the people on the other threads that have been helping so far (@Craiglxviii and @LostKiwi, thank you for your expertise so far), I've decided to move this issue to a new thread as I have also been having a conversation with @drmw about this...

I have a 2005 S Class on which the radio sometimes goes bang and switches off. All I do is switch the power back on and it works fine again for weeks or months. My current problem with it is that if I have the radio on, as soon as I turn on the heated rear window there is considerable...