JVM making buzzing sounds with standby off

[timcrawford]

Much different than the sound of a tube going bad I was shocked this morning to here a load buzz when I powered my JVM 205 up. I had just purchased the amp last week. I googled the conditions and got very few results, most posts called for checking tubes. To me the sound was completely different than a tube issue. The sound was coming from the main transformer. When I pressed down on the transformer the buzz got more metallic like. Simple fix tighten the screws around the transformer housing. Buzz went away. Tighten the output power transformer while you have the thing apart.

I added this post so JVM and buzz would be in one post... I did notice in my research that other amps have this issue as well. Might be a good practice to check the transformers like we do the tubes and bias upon purchase.
Judging from the thin metal used in the transformers I think it may be possible to over tighten, not sure. Not sure if Marshall has a torque spec for that...

I only got 5 minutes of practice in instead of an hour before work. Means I will be grumpy at work.

[surfnorthwest]

You have a ground loop issue sounds like to me.