The only thing I have found about this was here:
http://www.newbluefx.com/support/vegas- ??? 4-bit.htmlBut I suppose that won't help. Truth to be told, it can be pretty much anything, unstable version of Vegas, the effect, or the combination. My bet would be on unstable Vegas, 9.0 and 10.0 are pretty much considered a bit unstable on the Vegas forums, with 10.0 being a bit better in this regard (it's why I'm still using 8.0c and waiting for some major patch for 10.0)