I have a strange problem that has only just started. I have an Asrock ION 330 with latest mediaportal, drivers etc. Have always used SAF. Recently upgraded to 606. When I play back MKV movies (1080 or 720), sometimes the movies start, but then start to stutter and stall when playing. I stop them, and restart (stop, back to menu, play the movie) and they play fine. Media center is connected to my NAS using 1gb ethernet over 1gb switches. When I look at CPU utilisation during playback it's absolutely minimal. I'm using FFDShow DXVA decoder for video, and FFDShow for audio over TOSLink.
Any ideas?
Any ideas?