So i just got some new pedals (marshall guvnor, marshall supervibe and a cry babyGCB95) but when i plug them in a just get a faint whinning from my amp (which goes louder in distortion), when i turn the pedal off my guitar sounds fine but when they are on it just turns everything off. Im sure its not the pedals as the guy i got thm off demoed then before i got htem and they worked fine. Whats going on??

My Gear:
Ashton 'the rocker'
Peavy Audition 15w
erm, I don't really know much, but did you try them out through the same amp??
because that could be the problem, the amp not working well with the pedals
but like I said, I have no real idea xD