I am running:
smplayer 0.8.3-1~quantal1 (from the rvm ppa)
lubuntu 12.10
mplayer2 2.0-554-gf63dbad-1ubuntu0.1
amd64
kernel 3.5.0-23-generic
Basically, I use the spacebar to pause and unpause smplayer. Sometimes when I hit spacebar to unpause, nothing happens and I have to go ten seconds back and forth (using the arrow keys) in order to get it playing again. It is like it is stuck and I have to go back and forth in order to unstick it.
I mainly play mp4s, downloaded from youtube using youtube-dl, but this has happened with other media as well.
Any ideas?