I just recently had a situation where I needed to add a charge to my M-Audio Microtrack during a show, as I think the internal battery is on its' last legs, and the level was quite low early in the show. After it appeared to have taken a good charge, I disconnected the USB battery pack from the Microtrack - as I've been able to do in the past with no issues, and the unit went BLANK - deleting the entire hour and ten minutes I had just recorded! I booted the unit back up, and it recorded the rest of the show with no problems, and after the show, I tried connecting/disconnecting the battery pack again, and the unit continued to run just fine. I can't replicate the situation at home, and the only thing that I was doing differently at this show was that I was running a patch to another taper's backup DAT, from my RCA outs (lucky I was!), because we wanted to compare source recordings from our different mics/rigs. He suggested that maybe having the patch might have put more of a strain on the power source, which sounds plausible to me, but I honestly don't know.
Has anyone else run into any situations like this? I'm trying to understand what might have caused this, so hopefully, I can avoid having it happen again!