It's got to be some setting within Acid 3.0...if 2.0 is totally fine as well as any other program than you have deduced the bug at hand allready...I dont have Acid 3.0 so I couldnt tell ya what to try..
On the other hand...what OS are you running?
Opus

hmmmm... dont know about any of the other peeps, but to me, it sounds like a latency problem. Try the different soundcard devices in Acid's preferences.

I find meddling with settings gives me more information, you can always re-install the product right? :D

Do you have DirectX 8.0a installed? It is required for proper operation of ACID 3, and I know of others who have had problems with ACID 3 with older versions of DirectX.

Just be careful with new verisons of DirectX..some may cause more issues than you would want to deal with...also I'm wondering if that Core 2 is going to have any issues with newer versions of DirectX as well...that card has caused many people a huge headache or two...
Opus

The Core 2 is made by the Devil..Run ...Run far, far away.. :D

Originally posted by BrokenWindow:
The Core 2 is made by the Devil..Run ...Run far, far away.. :D
To quote the flock of seagulls...."And I ran...I ran so far away....I couldnt get away!!!!"

:p
Opus

I second the latency thing. All in favor say "I"

actually I've gotten reports that there are several people having the same sort of issue even tho they are using different cards..so it's not thge latency issue that is at hand
Opus