I've noticed this too. I have a few projects which were started by creating a few new audio tracks, duplicating these a few times to make about 16 tracks, and then recording or adding audio events to various tracks.

Now when working on the mix I have groups of tracks whose insert effects are linked so that when even only one of the tracks is muted, all of the effects are muted for the whole group of tracks. Again, I have not grouped these tracks; they were simply created by duplicating the same new audio track a few times.

These projects were created in Vegas 3 and I did some of the initial mixing before I bought Vegas 4 and I don't recall this behavior so it seems to be a Vegas 4 issue.

Now I have to go through the time consuming process of creating new tracks one by one and moving all these events and their effects to the new tracks. To avoid this in the future I just created a few default Vegas project files.

It's still an issue though when simply duplicating a track and wanting to do something different to the duplicate while the original is muted so I hope SoFo will address this in 4.0c.

Dave