Hartke HA7000 buzz issue - Help!

[storyboardist]

A couple months ago I got a used HA7000 off ebay and recently I've realized it has distinct buzz. I really only play it at church and usually I'm so close the the amp that the buzz is masked by the cooling fan, but it's a problem at the board since I'm also run an XLR direct out. I think it's coming from the power amp since it buzzes even when both pre-amps are turned down to zero. I thought it might be a grounding issue, so I made sure the ground lift was on and that didn't do anything. So I popped the top off and had a "dear in the headlights" moment upon seeing what's under the hood of this thing.

Any amp gurus out there know how to fix this? I think I'm starting to really annoy the sound guy.

Thanks!

[grendle]

Had that happen to my 3500 once. It was an outlet issue on mine. I got a ground lift plug and it fixed it. The ground lift button on the head did nothing in that circumstance for some reason. Gotta love those amps. Their not bad internally lol pretty simple, but if your not used to electronics.

[storyboardist]

Yeah I tried the ground lift plug as well and that didn't help. Also, yes, I know very little about electronics, especially amps. I can replace the input jack or a pot or something, but other than that...

Any other suggestions?