Bart, Lots of work. Thanks!! Did you mean 6.6 instead of 6.5? I assume you are running an Ubuntu 23.10 VM and not bare metal while I am not. I don't have any ideas either. My hunch is that this issue is very sensitive to delays. Perhaps our test boxes are a little different in terms of cpu performance. I am going to go back to working on rxe per se to try and move some patches that have been blocked for a long time. Thanks again, Bob