In case of connection of the external audiotrack, through some time (in my case about 5 minutes) video hangs up, and the sound plays further.
I noted that mplayer behaves also if to execute:
mplayer - audiofile ext_track - aid 0 videofile
if to clean -aid 0, works correctly.
Checked
the movie, direct reference on a torrent the file:
http://d.rutor.org/download/220371
audio track:
http://bit.ly/OpCr0P (on the right click "скачать")
PS: smplayer 0.8.6, mplayer 1.1.1, linux x64