Vista - Several problems with MediaPlayer

I am trying to use MediaPlayer controlled be MediaClock. I faced several
problems so far:

1. When I pay video clip, it stops few frames short of the end.
2. Event “MediaEnded� is never raised as for MediaObject as for MediaPlayer
inside it.
3. I tried to pause clip and use Seek() method. Seek() method in MediaClock
changes current time but does not update visual on the screen. If play is
resumed, it is resumed from the correct place.
4. Seems Add/Substract methods in TimeSpan do not work. Debugger does not
show any changes in “ts� in the code like this:
TimeSpan ts = (TimeSpan)Video.Player.Clock.CurrentTime;
ts.Add(TimeSpan.FromSeconds(1));
5. How to find frame rate of the clip?

I am using November CTP on WinXP.

Any comments?

--
Mikhail