Hi guys. I recently bought an mxr dyna comp used, off ebay, for about half the price they retail at. Extremely pleased with the tone and the effect it has on my guitar but i'm having some really strange problem with it.

I keep getting this random static sort of sound. It's not constant and only happens now and again. I've changed the batteries, ran it off the mains etc. Still no change. It can be fine for about half an hour or so and will start. It scales with the volume of my amp, when i increase amp volume, the noise increases. I can try and record a sample if necessary.

I really don't have much knowledge about the insides of effects pedals so i don't want to go messing with it, but any help would be greatly appreciated.

Thanks for reading.