In the last couple of months, it appears that mediacenter hangs a lot more often. It’ll hang on mkv and avi files and mediacenter will have to be restarted.
Occasionally, I’ll be able to successfully play the file on second attempt but more often than not mediacenter will hang again.
Also, possibly related, fast-forward/rewind on mkv files can cause playback to hang.
Right now I’m updated to the latest stable release but still no dice.