I think it would be easier for the folks here to help if you give us some more details... What platform are you on, Mac or PC? What OS? Which version of MPC4000 OS? Which version of AkSys? I've been running AkSys on PC for both the S5000 and the MPC4000 for some years now, never had a crash... It sometimes loses the connection to the sampler, but that is probably a USB-controller issue.
Anyway, some more details please, and then maybe we can help you out.
Cheers,
Arne S.

