FYI,
There is some problems with current release of 0.9.4 handbrake with transcoding and downmixing 48 khz source audio to N900. Problems occurs on both 48 -> 48 stereo and 48 -> 44.1 stereo . This can be tested with trailers from Apple. Sound gets really slow.

If someone knows quick and easy fix for this which can be used with handbrake please share your information.