Strange, but I have jackd 0.118, the latest update for JACK1. And there are some issues too. I’m not interested to use JACK2 now or in the near future (I need something more mature for a productivity environment and JACK1 is OK so far, but JACK2 seemed to be very experimental and unstable, I will wait 3-5 years before I use Jack2)
Renoise is great, but the JACK client is not realtime safe. Yes, this could be a bug report, I will make some more investigations and tests and then I will post this again in the bug forum.