Fault with speaker aux output - goes away with power cycle, then comes back

[JMUDoc]

I have a set of PC speakers with aux in and out. I plugged my headphones into the aux out and heard loads of crackle and bass blowout. I took the main unit (the other is a slave) apart and had a look at the aux daughter board, but couldn't find anything wrong, so I put everything back together and tried the aux out again, and it worked. Yay!

However, within a couple of minutes the fault had come back. It does not affect the main speaker output, only the aux, and a power cycle always clears it for a minute or so, but then it returns.

Any ideas on what could be wrong, based on this description?

Thanks in advance.

 

[Harald Kapp]

That could be a faulty solder joint, temporarily fixed by your manipulating the boards. Visually inspect the solder joints, re-solder any that look suspicious.

When you do a power cycle, do you leave the speakers off to cool down or do you immediately turn them on again? If the latter, a thermal effect is unlikely. Otherwise operate the speakers while open and look for any components that get unreasonably hot.

 

[JMUDoc]

That could be a faulty solder joint, temporarily fixed by your manipulating the boards. Visually inspect the solder joints, re-solder any that look suspicious.

When you do a power cycle, do you leave the speakers off to cool down or do you immediately turn them on again? If the latter, a thermal effect is unlikely. Otherwise operate the speakers while open and look for any components that get unreasonably hot.

The power cycle fixes the problem immediately - literally off-on, and it's back to normal.

I'm sure my board messing didn't do anything; it was the power cycle that I had to do to get access to the board!