I have found that 5.33 msec latency is too low for my system. I was getting a lot of xruns when I had it that low. I shoot for 11 or 16 (10.6 is my current). I can’t tell the difference and my sound isn’t choppy any more.
Also, the realtime kernel config might not be necessary:
Another point, something that I stumbled on, is this package:
This was the missing piece that fixed most of the issues I was having with jack. I am running Ubuntu 18.04. This package makes jack and pulse play nicely, don’t know what it is doing exactly. I don’t know your distribution, but it’s probably available in your package repos.
Lastly, make sure when tweaking your jack settings that those settings are actually being used by the sc server by reading the server boot output. I had some issues tweaking settings in
qjackctl, where the settings were not being saved out and the server was booting with old settings. It’s an issue that others have noticed. I think I eventually just rebooted my system and the settings took.