[XBMC] Audio problem when controlling with android

[effemmeffe]

I use Yatse on my android phone as a remote control for XBMC.
Everything goes fine until I try to change the playback volume using the phone volume buttons.
The audio suddendly changes to a lower volume and there is no way to have it back to full volume, even if I set the maximum from the phone.
It's like the volume control is overriding some default volume.
For example, let say I have a heard volume of 100, when I push the button on my phone the volume changes to 80. Then I can turn the volume to 0 with the phone button or return to a maximum of 80, but I'll never be able to return to 100.
On the log (http://xbmclogs.com/show.php?id=32535) I see some error about audio going in timeout, but I can't understand what does it mean.
XBian 1.0 Alpha 4
XBMC v12 Frodo – RC1
Raspberry Pi Model B