What is your dsp in this system? On the av2 I had issues with, the program was using BSS audio modules. The newest modules off of the BSS site would lock that av2 everytime. Reverted to some older modules and no more problems. I could load that same program that would lock the av2 and it would run fine on MPC-M10. I still would like to know why the av2 would lock though. The program was really small too: 80 symbols, 314 digital, 24 analog, 25 serial, so I know it wasn't out of memory.