PPI pro mos 450 pulses when powering on

Both times it happened in bridged mode, 4 ohm. The speaker wires have been directly wired due to the common missing plug thing.

I checked for front L/R, rear L/R separately, then bridged the front side to one speaker and the rear side to the other, as you're supposed to.

But I wonder if mixing these up would cause this problem, and there is some other wiring mistake in the inputs or something that I'm not aware of. I labeled everything ahead of time but say if the RCAs were reversed.
 
Before you clamp the cover down, press every transistor down and confirm that the transistor readily sticks to the heatsink without springing back up. If it's flat enough to be held down by the compound, it's likely flat enough.

Remember to look into the end of the amp to confirm that the tabs are being pushed up by the transistors when the screws are tightened.
 
OK I straightened a few bent tabs, added heavy compound below tape, added heavy compound on each device, straightened all devices to lay flat (just pushing each with my finger they stick down flat and stay), torqued down back panel very well. Ready to test again.
 
Like 3 or 4 songs in, sink is warming up little. Never played this long at least, so if it fails again I probably just need to go back and improve the heat sink mating more. I think it is really really good now though.

Thank you very much Perry for your help, knowledge, and patience.
 
I've been rechecking the clamp screws when it warms up.

It seems like it is repaired. Sounds very very good, better than I was expecting honestly.

I don't suppose anyone has a solution for the speaker output plug problem. I remember seeing somebody did a custom deal.
 
The spacing is a bit odd.

I know this probably isn't what you want but I'd remove and keep the terminal in case you find a mate for it.

Some people solder wires to the board and go out a few inches to a screw-type terminal strip. Something even easier, go out a couple of inches to male/female push-on connectors.

These aren't fancy but they do no harm, either.