I am experiencing the same issues with files that I have created using video editing in Photoshop CC. After rendering the files from PSD to Mp4's, and previewing within the folder, Bridge hangs and crashes. This is happening consistently whenever there's an Mp4 in the folder I've viewing, so I know they're not corrupted. I'm actually now creating a folder within the folder to "hide" the Mp4's thumbnail preview. This is the only solution I could come up with for the moment.
Can someone in Adobe-land offer some feedback or a fix for this?