Pioneer sa 9900

[David Robert]

I have a pioneer sa9900 amp which has started making a faint rustling noise in the left channel - after a while the protection circuit trips. If I switch it off and wait a while it works okay, then the cycle repeats itself

Does anyone have any idea what this can be - I've got the service manual but don't know what the problem is?

 

[chrisautosund]

noisy diff amp, probably 2sa725, replace them.