I don't get a scratchy sound once it's set, but I can hear static when I'm turning it up/down. I e-mailed Gary about it. Here's a thread: http://www.head-fi.org/forum/thread/497181/pa2v2-potentiometer-static-answer
I don't notice any imbalance at all. You can always e-mail Gary. He's a great guy to deal with.