Recommendations for amp repairs in London?

[razor5cl]

Hi all, apologies if this is the wrong forum to post this in but I tried searching for previous threads to no avail.

 

I've got an absolute behemoth of a bass head, a Peavey Mark VIII XP 600W from the 90s I believe. Used it in rehearsals and for several gigs, but now it makes a horrible buzzing sound when it's on. Sounds like maybe a grounding issue? The strange thing is that you get the hum whether a bass is plugged in or not, and muting my bass or using my tuner makes no difference. It's not loud enough to be heard at playing volume but as soon as you stop then it comes on.

 

I also previously had an issue where the amp would cut out entirely if the bass EQ knob was turned past a certain point so that probably needs looking at.

 

Seeing as it's unlikely to be something I can fix myself, anyone got any suggestions for someone I can take it to in or near London?

[tauzero]

Have a look in Repairs and Technical -