Alpine 3545 (alpines best) problems

[DerekB1]

Here is the problem... I have tried 2 different cd players, 2 different RCA's and 2 different cars so I know its an amp problem. What happens is that after volume 10 on the cd player the amp cuts every 5 seconds, it playes fine and sound is amazing but when it cuts every 5 seconds it gets very annoying. Please help, this is an awesome amp and I want to hold onto it for a long time.
Thanks,
Derek

[EnvisionAudio]

Several things go wrong in these amps.

1) There is a thinnish ground connection to a screw terminal that grounds the heatsink. Sometimes this ground connection burns out and must be jumpered. Without the connection, the power supply secondary sense circuit (say that 3 times fast) has an unstable ground reference and will pulse the supply at a particular current draw.

2) Solder connections at the emitter resistors are cracked (happens mostly with Pioneer, but sometimes Alpine).

3) Solder connections at the Toroid or Inductor filters are cracked.

4) UPCXXXX IC driver is momentarily sending the amp into protection. I can't recall the number at the moment, but it's a heatsink SIP IC that drives the output transistors. These go bad on a number of occasions and must be replaced. There is one of these per channel.

5) All of the above, or something completely different.

[N-Channel]

I believe the audio driver chip is NEC's uPC1270h. This seems to be the standard driver chip for all Alpine chips of that era.

Having owned a boatload of Alpine headunits, amps and EQs over the years, I have seen inside alot of the, and this appears to be the trend