When I render a file with original size sound is ok, but when I resize movie sounds stop to early and it is not synchronized with video.
( maybe it the same problem like: http://www.kdenlive.org/forum/moved-audio-after-rendering )
I see this problem in webM and h.264 ( not tests other )

I'm doing the same quite often and have not seen this issue. Only one time where it was related to strange frame rates, but not to scaling.
As a workaround I would try to first render to a lossless format in original size, and then render scaled to the final format, maybe that avoids the issue?

I know where is problem.
I have movie from camera -> 29.970030 ( i use VLC to read it ), so i always select profile 29.97fps, but it is wrong!!!
When i select 30.00fps sound is ok :)
( i didn't check problem from link my first post, with this settings, maybe it's the same problem )
EDIT:
A, it happend only if a rescale movie, when i render with original size everything is ok