I personally haven't had latency problems, even when my computer wasn't as fancy, but I have to agree that that's where the problem would be. The way my setup works is I run all my mics into my mixer and all my Pro Tools tracks are set to go out of two outputs, which go to the main stereo input on my board. That way, no matter what is going into the board, the main stereo input can always be heard. I plug my headphones into the mixer. Then I can hear the mic as it goes into the board (so before it goes to the computer, thus no latency) and I hear the outputs of my computer as they hit the board, too. I think with that setup, you should at least be hearing everything at the same time. I hope that wasn't too confusing...