My A4000 audio died in exactly the same way. It started making that exact noise in the left channel, but at the start it would only do it every now and then..
"*pop* cracklecracklecracklecracklecracklecrackle *pop*", but it started to do it more and more.
Now, the left channel just crackles like that all the time, and the actual Paula audio is very quiet.
I think it *is* the capacitor problem, but the surface mount caps used look quite difficult to replace to me :-(
