Kcarp
Its stops working after a while and there is no way to get it going again. Even Cakewalk support do not know or will not help. I have mixes to bounce for clients that now instead of a carefully fine tuned lead are now just ear splitting noise!!!!
I did a clean install and it fixed my z3ta+ here.
Running 10.6.8 on a MBP 15
Maybe try cleaning out everything and installing again?