Broken amplifier help, Cambridge

guitarmangler

My much loved, and used, yamaha dg80 is on the fritz. 

Does anyone know of any amp or electronics repairs Cambridge? 

Currently the amp turns on, I can see the pre amp working. But I get very little output. Then occasionally it will jump back to its usual killer death level. I’ve tried servisol on the pots. Running a lead through fx loop. Sometimes it works. Sometimes it doesn’t . I have a gig on Friday. Might have to go direct and use in ears at this rate!

Onpar

Hamstead amps. Peter is a gent and very knowledgeable.