Hi folks, I've been looking for a way to add an aux in to the beat, and I've cracked it!
It's turned out to be really simple if you have a cd autochanger.

I opened my spare one and spotted 3 test points, labelled as left, right and ground.
I chopped up an old 3.5mm jack cable and soldered it to them, made a cd with just one track (Mr cages 4'33" of silence), popped it on repeat and played my mp3 player into the jack...
Tada! A working aux in! Click image for larger version. 

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