I have seen that I can control the speed of vlc by using the keyboard shortcuts +/-. It works to play the movie slower with [-], but I can't get it to play faster than 1.00x with the [+] keyboard shortcut. This is with vlc run as
cvlc file.mkv version 2.0.3-0ubuntu0 under Ubuntu 12.04 x86.
I am doing this on a laptop, so the only '+' sign I have is in the [+/=] key.