Sparks flying in Parasound

[dude2010]

I know this is odd, but never the less true!
In my Parasound HCA 2200 MK II sparks fly when turned on.
Front facing you, it seems to come from the upper right boards backside. Dismantled nothing on board, nothing to see, vacuumed still same thing.

Nothing in the sound, nothing in the speakers.

It's provoked slightly more when warm, shut off for a min to change cables, and then back on. Then I simply pray to the hifigod, not to leave it in flames.

HELP!



View attachment HCA2200II.pdf

By the way if you know this construction, you know the sound - and the sound compared to others.
When I compare it to my DOXA 73 signature, a not too powerfull 70W highend poweramp or other amps for that matter. The Parasound sounds compressed, but even worse, it seems to have a phase reversal in the midtone or crossover fuckup somehow. When the powerplug is reversed in the socket, it sounds even worse, kinda the other way around.
What can that be?

 

[unclejed613]

if you are talking about the board with the 0.22 ohm resistors on it, maybe you have a hole in one of the output transistor's heat sink insulators?

 

[dude2010]

if you are talking about the board with the 0.22 ohm resistors on it, maybe you have a hole in one of the output transistor's heat sink insulators?

You can take a look at the picture, it's the board on pictures upper right hands backside. Parasound says it can be a screw that's loose..

Could you take a look at the added Q in the top?

 

[DF96]

A loose connection carrying high current (e.g. initial charging of PSU electrolytics) can create sparks. I would expect some noises to continue, unless the circuit has exceptionally good PSRR.