rncbc
commented
9 months ago you're running qjackctl as a pure jack-client, possibly due to pipewire-jack substitution.
when in this mode, presets and all settings but buffer-size are disabled and in fact meaningless; presets and settings parameters for that matter are only meaningfull to genuine jackd(bus).
In qjackctl 0.9.12 from official Arch Linux package, the Setup dialog looks like this:
Everything on the Settings page except for the Frames/Period field is disabled.
In particular, the UI near the top that looks like a preset manager is disabled in its entirety andcannot be used. I fail to discover how to create a new preset, one that I can actually modify, and more importantly, make persistent.