This is driving me nuts. I see that this is not a new problem and dates back to 2005 but the threads I found do not reach any conclusions. There are suggestions that sound cards and or plug ins aren't flushing their buffers but there are no conclusions or fixes mentioned. http://forum.cakewalk.com...age=1&key=%F1%A2%8D%90 http://forum.cakewalk.com...7784&high=reverb+tails Unchecking "play effects tails after stopping" does not fix the problem. (It doesn't prevent effects tails from playing after stopping either.) Does anyone know a solution? I'm using 7.3 PE on a Windows XP machine with an Alesis io26 interface. Thanks.

The only fix I've found is to play and listen before you mix. If you hear it, wait, play again etc.  
If you don't hear it, it's not there. PITA.

In a way I would think this does not happen anymore with the advent of 64 bit and lot's of memory etc.
I remember getting glitches and things like your talking about, but that was a few years ago now. Just sayin'

The best way is to let your project play until everything fades into silence.

And the way to achieve this is to select a clip - any clip - and extend it's right hand edge up to the point where you have silence at the end of the song.

Then, Sonar will continue to play for the entire length of your song, including reverb tails etc, and they won't intrude into the beginning of your export.

Or close the project and re-open it before exporting. I like to do that not only for clearing out delay/reverb buffers but also for freeing up memory that's been allocated for soft synths and generally resetting everything to a clean state.

Thanks for the input gang. Some decent work arounds here but still a bit of a pain. Oh well.... And, yeah Cactus, my gear is 5 years old. 2 gigs RAM but it serves me well enough. Cheers.