sorry about that new to this:
windows 7 ultimate
alienware 15x laptop
i7 cpu q720
64 bit os
version pms: 1.81.0 Build: 5b9f782ef (2013-04-21)
engine: tried mencoder, ffmeg, vlc
In detail, as per my post above, no mkv will play that i can find. i have tried more than 20 different ones. ffmpeg does exhibit the same stop start behaviour as vlc although vlc is slightly better. mencoder doesnt work at all.
let me know if you need anything else.