Recently I went 64bit and tried to load a project created in 8.0c into the 64bit 8.1,- this produced a message for each of a number of files saying "<FILENAME>.m2ts has changed enough that themedia stream properties from the project files could not be applied. Default media stream properties were used." The audio synchronised to the video had VANISHED (although non-synched audio elsewhere in the project was audible).
I should add that I'm using Windows 7 RC, though it is not on my list of suspects as I find it pretty good and reliable.
