I have originally reportet on launchpad and copy here the header of the report:

Unfortunally I have no stacktrace of this.

https://bugs.launchpad.net/ubuntu/+source/totem/+bug/1030069
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totem get sometimes a frozen video(flash) picture when playing the video in fullscreen mode.

Sound is still playing further.

The controll elements of totem do not appear when the mouse touches the periperie of the screen.

A reliable reproducing procedure I can not give, because it only happens sometimes.

Reproducing try:

1.Insert a dvd with flash video content
2.Open nautilus and choose a video
3.double click -> Quantal starts totem by default
4.When the video is running switch to fullscreen mode
5.May be you see the issue described above.

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: totem 3.4.3-0ubuntu1
ProcVersionSignature: Ubuntu 3.5.0-6.6-generic 3.5.0
Uname: Linux 3.5.0-6-generic x86_64
ApportVersion: 2.4-0ubuntu5
Architecture: amd64
Date: Fri Jul 27 19:58:00 2012
ExecutablePath: /usr/bin/totem
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Alpha amd64 (20120722)
LogAlsaMixer:
 Simple mixer control 'IEC958',0
   Capabilities: pswitch pswitch-joined penum
   Playback channels: Mono
   Mono: Playback [on]
ProcEnviron:
 PATH=(custom, no username)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: totem
UpgradeStatus: No upgrade log present (probably fresh install)