I am unable to get jack to start with realtime kernel priority on Leap 15.0,
this was working on Leap 42.3 after boo#1053777 was fixed.

simon@tek-master ~ >  cat /etc/security/limits.d/99-audio.conf
@audio   -  rtprio     99
@audio   -  memlock    unlimited

I'm still using Cadence to start Jack.
https://build.opensuse.org/package/show/home:simotek:multimedia/Cadence


Tue Jul 10 16:21:43 2018: ERROR: Cannot create thread res = 1
Tue Jul 10 16:21:43 2018: ERROR: Cannot use real-time scheduling (RR/99)(1:
Operation not permitted)
Tue Jul 10 16:21:43 2018: ERROR: AcquireSelfRealTime error

Bug ID	1100734
Summary	No longer possible to run Jack with realtime audio in Leap 15.0
Classification	openSUSE
Product	openSUSE Distribution
Version	Leap 15.0
Hardware	Other
OS	Other
Status	NEW
Severity	Normal
Priority	P5 - None
Component	Kernel
Assignee	kernel-maintainers@forge.provo.novell.com
Reporter	simonf.lees@suse.com
QA Contact	qa-bugs@suse.de
Found By	---
Blocker	---