Okay, I got the shroud off the cart connector and cleaned the pins - didn't really make a difference. But I noticed that if you leave the system on you'll see a flickering splash of color every now and then, real faint and gone in a flash. And occasionally it will look as if it's losing power, like flicker halfway off. SO I'm curious about the power adapter now. I don't have a multimeter, but I may pick one up to check the voltage on the adapter.
Any thoughts, let me know...I'll update with my findings.
EDIT -- I forgot to mention I messed with the pots too, and it made no difference whatsoever.