Here's the response I got from Behringer
Hi Eric and thanks for writing to us!
First I would recommend turning OFF the power amp (to prevent any more potential 'pop' sounds while you are troubleshooting and turning things on/off from reaching your loudspeakers), and then attempt a factory reset on the unit by the following steps:
1) press & hold keys "compare" and "memory" during power up.
2) confirm reset by pressing "OK"
Then leave the unit on for an extended period of time, such as overnight or while you are away at work for the day, to try to reproduce the error message symptom (again you may want to leave the power amp turned off during your testing to avoid the possibility of the 'pop' being amplified to the speakers again).
If the error message still occurs after performing the factory reset procedure above, that could indicate a DSP error within the unit, and I would recommend contacting the dealer to see about making arrangements to exchange the unit for a replacement at your earliest convenience. Or,
if exchanging the unit for a replacement through the retail dealer is not possible, please use the instructions below to get in touch with our warranty service department and we will be glad to help you make arrangements directly through BEHRINGER.