Haven’t made it happen yet. Mint 19.1 on an ASUS Sabertooth 990FX w/ 32GB. Up to now the only audio on here has been from the media player – some *.flac files – and concert music on Youtube.
I know linux well and have background in audio synthesis (long ago) and 20 years in software engineering. JACK is evidently present on my machine; qjackctl runs, but doesn’t find anything to connect to, in or out. The audio hardware is just whatever’s on the motherboard.
I’ve made small changes to the initial VCV-Rack patch, and observed their consequences on the scope (added an LFO to provide gates to the ADSR, noodled with the a.d.s.r. parameters to confirm they work the same way they did forty years ago, and so on).
I tried installing the skjack plugin. But nothing came of that – I couldn’t confirm it had even been downloaded – didn’t find any evidence in ~/res or in ~/.Rack.