Any Korg KP3 users? Ground issue?

I have a KP3 that I run my Mp through, but I'm having trouble with subtle popping sounds when I lift my finger off the pad. For a long time I thought It was a looping issue, so I finally unplugged everything and ran a single sound source into it and the problem still exists. I've also checked the outlet to make sure it was grounded. If your reading this, and you have a KP3, try using the first loop effect with any sound source and see if you can here subtle pops as you slowly tap the pad... Driving me nuts.

could be a grounding issue... wear your shoes and try it again haha..