Whenever I attempt to play a video (or an audio file) with Totem I get the following error: "totem invalid commandline The parameters passed to the application had an invalid format. Please file a bug! The parameters were: --transient-for=75497483 gstreamer|1.0|totem|H.264 decoder|decoder-video/x-h264, level=(string)3, profile=(string)high, stream-format=(string)avc, alignment=(string)au, parsed=(boolean)true" I've added the gnome3 team's PPA if that matters.
I ran into the same problem as you did. So I tested my video playback (mp4, h264) with VLC and it worked very well. But I wasn't able to have Quicktime playback in Firefox with the
So my advise to you would be to use