Rexaronie,
If you just purchased a TASCAM unit I highly recommend you return it. I just got off the phone with TASCAM support, again, and they told me to return the unit. I've had two already (US-800).
I know the price is attractive on these boxes, but there is a reason for the price being so low...
I exchanged mine for a PreSonus Audiobox 44vsl and have had no trouble all day long, running Lion 10.7.3. It cost me an extra hundred bucks, but it is worth it. The US-800 was driving me absolutely nuts.
The TASCAM is a royal PITA and does not work, you'll spend all your time trying to figure it out but it just doesn't work. Phone support is a waste of time since they have zero ability to do anything except tell you to try a different USB cable.
Honestly a terrible experience and I'm surprised that a name like TASCAM, which has been around for ages, has such a terribly supported product on the market. The hardware seems nice enough and is really cheap, but what good is cheap if it doesn't work?