I had an odd problem yesterday- I uploaded all of my recordings from Friday and Saturday to my hard drive and deleted them from the SD. I probably should have re-formatted, but I didn't. I had not completely filled the card. When I started recording on Sunday, it managed to reset itself to internal memory and subsequently crapped out after 2-1/2 sets. It took me a bit to figure out why it shut down- I changed batteries then it said "memory full" so I thought maybe I needed to clean up the deleted files or something, started looking for a recycle bin to dump or something but finally hit on the memory setting and saw that it had been reset to internal.
So, has anyone had this problem and do I need to check the status of this setting every time I record?
Other than that the recorder was pure joy to work with and runs longer than all day on a pair of AA's, either alkaline or NiMH.