It could be dual core specific problem: http://www.archivesat.com/JACK_developers/thread610991.htm
Some quotes pasted here: "I've got similar hardware and Lee's right, the "-clockfix" branch of jack CVS fixes this problem. The root problem is that the TSC clock sources on the AMDx2 cores are not sync'd, therefore time, as perceived by JACK, can appear to leap forward or backward as the process migrates across the CPU cores. The -clockfix branch works around this "feature"." "Just make sure the kernel is not using the TSC for its own internal timekeeping. " -- Jackd, after started, stops after few seconds https://launchpad.net/bugs/67214 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
