1) Folder Monitoring starts adding lots of new tracks (I also have analyze volume & duplicates enabled)
2) Start playing a song. (Not sure if this step is needed, but that was what I was doing at the time)
3) Select a genre, artist or album which contains only a few tracks. This makes it easier to see the result of the bug.
4) Select a file and hit F2 to start inline editing.
Result:
1) Inline editing is interrupted.
2) The file that was processed in the background at this moment is added to the end of the filelist.
I repeated this a couple of times, hitting F2 and kept getting interrupted. After doing this a few times I got an "access violation" error and after that inline editing stopped working completely.
System:
Windows 7 x64 SP1
Media Monkey Build 4.0.3.1473