I think you should put some type of rule that says if it is in the “Music” folder then it is more likely to be an audio file else it is a video file.
It is a Sansa Fuze + running 02/37/01A and it happened on EVER single firmware version I have tried so far/
"Hello, I reporting the fact that .m4a audio files do not display properly if a data transfer unrelated to the file occurs or if you reset the player.
I shows the files under video and it gives the titles of those file but the time is always 0:00. Whe I try plaing it from the video, when the rror occurs, It says unsupported format. In the manual it states it can play m4a/m4v and AAC files. If I remove then add the songs again it works properly by putting under music. You really need to fix this.
Also I have experienced this on ALL firmware versions including 02.37.01 A" Saturday 4/30/2011