bad video playback and audio out of sync

I am having problems with video quality in PSE, I have many camcorder and phone videos in my picture library and many of them either look bad or the audio is out of sync. The photo management part of this software looks good but the video part is just not working right. I tried un checking the option to use the video card to playback video but it still has the problem. Is there a way to select an external video play when trying to play videos? all my videos play fine in other photo software so im pretty sure its something with this program. Also when I click on a video from the Media section it says preparing video for playback, what is this all about? Is it converting my video just to play it.

Thanks for any help.