Hmmm. If we make the pretty reasonable assumption that the volume control is a dual gang pot, I'd still guess dirty contacts. Have you tried (with the power off) turning the volume up and down vigorously a few times? In the past, I've had components that had pots with silver contacts and now and then you'd have to work the oxidation off.
Scratchy pops coming from the left channel when I turn up the volume why?
I have a Counterpoint 3A preamp that I am getting this scratchy popping noise coming from only one channel (left) when I turn up the volume. I took off the faceplate and sprayed the volume pot with contact cleaner but it still there. I am surprised that with the volume that it not both channels? Any help would be appreciated.