Thanks Guys, It worked! I'm not actually running TDM mode, just letting Logic access Core Audio. If you don't mind, I have another question... When composing a song, and needing a buffer of 512 to avoid pops and crackles, how do you switch to a buffer of 128 or 64 for recording vocals to those tracks? I'm just wondering, because even with low latency on, the vocals sounded more instant on 64 then say 512 or even 128. Thanks again, Les