I have a 2005 malibu maxx and i keep on getting a check DAB message right after start up. What is DAB.?

I don't have my Owner's Manual handy, but as I recall it's Digital Audio something. It's one of the electrical gremlins on the '04-'05 Malibus. On my '04 Maxx, I get that message infrequently, usually only when XM can't find a signal on startup. Assuming I'm not in a rush, I turn the car off and then on again and it's gone 99% of the time. I think the warranty fix was to replace the radio, but I never bothered. In any event, it's nothing other than annoying.

Update: The Owner's Manual says that this is a hardware failure and that the receiver may have a fault and that a dealer consult is required if the message doesn't clear within a short period. It doesn't say what "DAB" is.