Hafler DH-500 shuts down after 4 tunes

[PapaZBill]

A friend asked me to look at a Hafler DH-500. I have yet to see it.

He's complaint is the amp shuts down after four songs. He thinks the thermal protection may be causing it, but the amp is not getting hot.

I know this info is minimum, but was hoping the issue has been addressed before and whether someone knows what the fix might be or
where to start.

I'm an Electronic Tech by trade and have worked on audio gear for 30 plus years.

Thanks in advance. Bill KR3LL

 

[RM]

He didn`t mention the tunes, or their accumulated playing time?

R

 

[rayma]

Use an IR gun to look for hot spots under load.
How is the bias set?