Marco has a point if auto ripple is on then the still end up moving together - definitely confusing. Just to be on the safe side. select both video and audio , right click then > group > remove from U should do the same though
I think I found a solution that might work (it worked for me).
Step 1. Put your video/audio media in the timeline, of course.
Step 2. Do either of these:
A. Delete the audio track (which removes the audio from the timeline and not the video), add a new empty audio track, add the same media again, add a new empty video track, place the video part of the video/audio media (not the one with the video alone) in that new empty video track, then delete the added video track to remove the video (leaving only its audio).
or...
B. Delete the video track (which removes the video from the timeline and not the audio), add a new empty video track, add the same media again, add a new empty audio track, place the audio part of the video/audio media (not the one with the audio alone) in that new empty audio track, then delete the added audio track to remove the audio (leaving only its video).
Step 3. Move both of them together (the separated video and audio) to make it look unchanged.
Finally, Step 4. Move either freely to notice the two aren't moving together.
Ok. It seems the "remove from" method works on the Platinum edition (and I'm guessing the Suite version, too). I guess it doesn't work for the normal version.
OK, so you don't need those tips any more. Anyway, read Method 3 in the msz link. It might come in handy sometimes. And note that you don't have to be guessing about the Suite either as it includes the same Platinum.