Thanks for the reply. I double checked, the VST plug-in is for Silicon Macs. And I am running MC 28.0.96 as Apple native, not through Rosetta (Activity window shows 'Apple'). The plug-in works in Reaper.
I removed and re-installed the plug-in. (FYI it is VST3) Same problem - After installing it on the DSP page, when I click on the plug-in I get an immediate crash.
One thought I have - the JRiver wiki instructions say:
-Open DSP Studio
-Click Manage Plugins > Add JRiver, VST, Winamp Plug-in...
-Select the VST DLL from your filesystem
But I have a VST3 plug-in with file extension .vst, not .dll
Is this a problem?
There seem to be others getting hard crashes with VST3 plug-ins
https://yabb.jriver.com/interact/index.php/topic,126706.50.html