It's the preamp. The amp is fine. I took the cover off the preamp and started poking around. While tapping around, I came across a switch. Not sure what the switch does but as soon as I tapped it, there was the thump. I've shut the system down to let everything discharge. I'm going to blast the switch with some canned air, move it back and forth a few times and see if it's gone. I've talked to Rogue. If I am not able to fix it myself, they will do it for me. At least now I'm pretty sure what it is.
