Audio when using passthrough dont start

I have the same problem in both xbmc 12.1 and 13 that the audio dont start in passthrough
until i skip fwd/back couple of times. Then the audio start and when the audio dont start the movie goes
fast, i guess that has to do with audio syncing.

It does not seem to release the audio resource properly sometimes also because i get no sound when i exit xbmc.
Then i need to start it again and start something with sound and then exit again.

I run:
Ubuntu 12.10

HW:
Acer aspire revo r3700 nvidia ION
The ouput is HDMI to my reciever.

Any ideas ?

/T