bon j'ai trouvé la solution:
c un problème lié au click droit et à la commande "play on my tv" (dans le fond du menu click droit) je l'ai viré et je ne sais plus c quoi en français
toute l'explication ici : (trouvé sur un forum anglais à l'add suivante : http://www.techimo.com/forum/t117062.html)
shadow78 : "I was also experiencing these annoying sync-problems. The cause for this lies in nvcpl.dll - a nvidia dll, which scans for connected TVs.
The first time the dll is loaded, is at windows-bootup (HKEY_LOCAL_MACHINE->SOFTWARE->Microsoft->Windows->CurrentVersion->Run).
This causes the first flicker and unfortunately the auto-startup-entry can't be deleted.
The flicker when right-clicking on video-files is caused by a shell-extension, which the nvidia-driver installs for all types of video-files. This shell-extension calls nvcpl.dll everytime you right click a video file to scan for connected TVs. If a TV is present, the shell extension shows up in the context-menu as "Play on My TV". I never tested this, but I suppose when you click it, the video is directly shown on your connected TV.
This could have been implemented a lot better, this f...ing sync-flicker is driving you crazy when browsing a video archive.
After scanning the registry, I found the key responsible for the shell extension. Just search for "PlayOnMyTV" in the registry and you will find some entries under "shellex" (shell extension). These entries contain an identifier, {FFB699E0-306A-11d3-8BD1-00104B6F7516} in my case, I'm not sure if this identifier is static or created dynamically, so in your registry, it might be another number. Now copy the identifier and search for it in the registry; delete every occurence when it's connected to video-file formats (.avi, .mpg, .mpeg and so on) and afterwards the "PlayOnMyTV"-shellextensions.
That's it, now the flicker when right-clicking on video files should be gone (at least it worked for me ). I hope nvidia fixes this annoying issue asap, not every user wants this (unnecessary) extension and it causes very annoying problems. "
pour moi ça a marché j'espère que ça en aidera d'autres