xbmc can't seek when reading mkv from dvd

Hello

I've some trouble reading a big mkv file from a dual layer dvd:
- playing file stop at mid-movie (presumably when switching dvd layers)
- I cannot fast forward (by dragging the small vertical bar).

for the second point, xbmc.log shows:
19:41:35 T:140007966426880 WARNING: CALSADirectSound::CALSADirectSound -
device is not able to pause playback, will flush and prefix with 8183 frames
19:41:44 T:140007966426880 WARNING: CALSADirectSound::CALSADirectSound -
device is not able to pause playback, will flush and prefix with 8184 frames

This problem does not occur after a "cp /media/stuff/big_movie.mkv
/elsewhere". I guess that the seek can be done if the file is cached in RAM.
Once the dvd is ejected and reloaded, the seek does not work anymore.

This seek problem makes reproducing the first issue problematic (there's no
such issue if the mkv file is cached in RAM either)

Can anyone confirm this behavior ?

I'm using xbmc/unstable: 11.0~beta1-0.0

Happy new year !

All the best