Maybe crackle is not a good term to use. I would say distorted
sounding. Almost like overdriven input to a soundboard or a blown
speaker (but its not that). Well I resoldered all joints on heatsink
and many of the others while I was there. No improvement or change at
all. Re-checked with headphones and left and right sound great! Does
that eliminate the circuitboard behind the front panel and focus us on
the board with the heatsinks? By the way what do the 2 big caps at the
back of the unit do?
Are they a filter of sorts? In my pinball repair they have used them to
stabilize voltages.
Wish I had some info the the test points TP1 and TP2. I wish I knew
what componets are used for the left channel, I could replace some and
hope for the best. Any other leads appreciated. Thanks Everyone Dave