phantom file number

While shooting in raw+ each file had a corresponding file .jpd and dng except one file which was stored as a jpg but a strange number:

_K5_1121.dng and _K5_1121.jpg

no dng file _K5_M1122.jpg

_K5_1123.dng and _K5_1123.jpg

Any clues as to what caused this. The jpg with the M added was decent enough and was the only one to have this "error" out of 80 odd snaps.

Probably M for Magic

Possibly something that you might have pressed that's saved a
dump of the last file taken.... such as preview or DPF preview.

I've never had any like that. Perhaps I should complain

Did you turn off the camera too soon after taking the offending shot, in which case it may not have had time to save away the dng file

regards
Bernard

I'm not sure what I did. Is the jpg generated first from a buffer and stored then the dng file saved, if it is it would mean that to put the M in the file name it must be able to tell the future or behind the scenes processing goes on when the the switch is turned to off. I'll try doing that with another card a slow class 4 click then off.
Wonder if I "chimped" to soon :