[labusas]

I would like to pick your, kind gentlemen, brains a little. I have a problem with my DIY amplifier. After a speaker cable short one of the modules developed a loud static, crackling sound (like FM station out of tune while playing loud). I can still hear the music playing and the noise is still there with no input wires soldered on. The noise is louder when input wires are connected and even more loader when I start playing. At switch off I hear a load pop, which is way loader than normal.
I ruled out cables, source and volume control. It must be amp.

I started gradually replacing semiconductors starting with small TO92 devices, then 2SC1819 NPN. That didn't help. I also re-soldered my module with no improvement.

All the voltages are within range, those that I measured anyways.

My question is it possible for caps to do that? Could it be transistor drivers
Maybe output transistors NPN or PNP pairs are on their last legs?
Thanks for your input in advance.
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[JoshK]

My *guesses*:

#1 it is your tweeter....try another amp, borrow from a buddy or use a receiver if you must but try out another amp to rule out a blown tweeter or cap in the tweeter xo.  

#2 it is a bad cap in the amp's PS or coupling cap.  This is a guess mind you, I am no expert but from what i have read this sounds equally likely the culprit.  Sometimes though the caps shown signs when they are blown like leakage, etc.  Look around, take multimeter to a number of parts around the suspect area.