I'm glad I'm not the only one wrestling with the Zi8 audio issue.
Anyway the first two steps are these:
1) Go to Options and Select "Ignore Event Grouping."
2) Grab the left (beginning) edge of the audio event and pull it downstream exactly 2.000 seconds.
When I grab the audio event, it still moves along with the video event.
I added another video to another track. Deleted that video, leaving its audio (because I still cannot delete/move just the audio). Now when I move that audio, it moves the video from yet another track!
Again, there is no "grouping" and choosing the Group menu, with any of these objects selected, has all the menu options grayed out.
Curiously, moving the video left and right does not pull along that audio object.
Therein lies the rub. I am most certainly selecting the event(s).
I've edited with Vegas dozens of times in the past. Grouping and ungrouping worked just fine. It doesn't anymore and it is boggling my little mind as to why it doesn't.