Help! 'escape' key combination for Tascam DA-3000


In folder view, I've tried to delete a single file of around 10mins duration. 

Previously, the 'deleting' screen pops up for a few seconds, then the file is deleted, and the machine returns to folder view. 

The 'deleting' screen has been active, with the whirring reels, for over quarter of an hour now .... does anyone know of any emergency 'escape' combination of keys I can use to abort the action, or will I be forced to power it off and take my chances on whether or not the whole memory gets corrupted? 
tascam3000user
Panic over. After about half an hour, track deleted, and back to normal
I had this problem once, and thereafter followed instruction in the manual to turn the unit off when inserting or removing a memory card.  I also upgraded to 2.0 software, which according to the manual resolves instability. 
" thereafter followed instruction in the manual to turn the unit off when inserting or removing a memory card.   "

OK, thanks, but I've inserted one card and left it there for the whole life of the machine. Never removed and reinserted one at all, whether with power on or off

I'll look into the software. 

Thanks again