Through a painful process I'd rather not go into, I discovered that Jack will not run in realtime mode with my Radeon's 3d drivers loaded.. I get the error "cannot lock down memory for RT thread"
My idea-for-the-day was visualisation of realtime jack audio (from live performance); needless to say my day ended up far less interesting than I had hoped. :) Is this a known problem, or screwy system configuration on my part? (XFree-4.3.0, Radeon9000 Pro, Linux 2.4.24 lowlat) -Dave