Cambridge Audio Topaz AM1 Problem

[Surtsey]

I have a Cambridge Audio Topaz AM1. Occasionally a buzzing sound can be heard coming from inside the amplifier. If I tap the case, the noise stops. Any ideas?

 

[Netlist]

Any ideas?

Bad solder joints.

Hugo

 

[Puffin]

Sounds like transformer hummm to me. The transformer is likely bolted to the chassis with a bolt through the middle and a rubber washer underneath the tranny. Sometimes tightening the bolt helps stop hum, but it may not remove it all. It could also DC on the mains.

 

[Netlist]

Indeed, I read too quickly.
If the buzz doesn't come out of the speakers, Puffin certainly has a point.

Hugo

 

[Surtsey]

Thanks for the replies. It's not mains hum. I'll check the transformer and solder joints. Does it have relays?