[LAU] ZynAddSubFx audio jitter, no xruns

I'm working on setting up a dedicated music box at home, and am running into a strange issue with ZynAddSubFx, I picked very non aggressive settings while trying to eliminate the jitter problems . First here is my setup: Ubuntu 8.10 2.6.29.rc6-rt3 kernel jack 256 Fraames/Period Sample Rate 96000 Periods/Buffer 4 Realtime Midi Driver: seq resulting latency 10.7 ms Maudio Omni i/o with Delta 44 sound card (ice1712 driver) Maudio Axiom 61 midi keyboard When I use qsynth with a soundfont loaded in it, there are no xruns, and no audio jitter. When I use zynaddsubfx there are NO xruns, but there is audio jitter. I thought I saw news on the list of a new release of zynaddsubfx, but the last update on their sourceforge site was in 2005. Anyone on the list ever see this behavior from zynadsubfx.