Been using a us-1800 tascam interface to record live instruments on my imac...and it worked for like a week, BUT now no workie. I can't get the computer to connect to it. When i open the tascam software it says "Device: None Found". I've tried everything...reboot, reinstall driver, switching everthing off and on, but no dice. I'm using garageband and it showed the tascam channels in the input menu before i lost the connection and haven't able to restore.