Hi there -

I've had a similar thing in the past - though I had a MOTU 828 running through the firewire port on an audigy at the time, on XP Home. I don't think it crashed my machine when I got the message, but playback wouldn't start. Possibly the machine would hang for about 10 seconds (vegas anyway) before the error message would come up? Anyway, try these (I THINK they might help...you can only try, right! :)

1) I'm assuming you've changed the default vegas setting of 'Microsoft Sound Mapper' in the Vegas audio preferences. Here you can also change the defualt device that vegas uses. Have a play with this if you have more than one sound card (ie other than the RME setup).

2) Have you got the preview fader and master fader set to feed the RME setup. Possibly if you have another soundcard in your PC which is set to be Windows default (Control Panel>Sounds) then Vegas has assigned this to the Preview fader, and it might not like the sample rate you're using. I know it shouldn't really be used when playing back a project, but I think Vegas opens up/takes hold of the Preview port anyway.

3) The obvious one - does the RME support the sample rate? Do the settings in the RME control panel for bit depth and sample rate match those that you are outputting from Vegas?

4) If you do have a second sound card, try using this in vegas and see if you can avoid the crashes.

5) Is Vegas the only app open? Has another app set the RME drivers to a different bit/sample rate? It might help to turn off all of the 'internal' system sounds (like for the alert boxes) that windows spits out. I think they are all at 22Khz, 8bit (maybe 16) and when they play they for the sound card to uses this rate, which might then cause your problem in vegas (point your finger at the MS starup sound!) If you want the system sounds and have a 2nd sound card, tell windows to use this as the defualt device - the sounds will play through this and leave you RME running at your preferred settings.

Hope this helps

Mike K