I currently have a Tascam US-122 and am looking to upgrade. I would like S/PDIF ins and outs and don't want to spend more than $250-300. Also, it needs 24-bit capabilities. Some of the M-Audio FW stuff is appealing, but I have heard there are problems with the drivers for OS X and are just problematic. Any ideas?

My us-122 is all messed up right now. It started with the left side just not working one day and i haven't been able to figure out how to fix it or where to fix it. Now on top of that everytime i plug my condenser into the right side and turn the phantom power on it makes a fuzzy hum noise that is like -5 db. really bad!