ZynAddSubFX not functioning

I noticed the problem with 6.3 first a couple of weeks ago. When assigning Zynaddsubfx to a midi track the following happened

Within the Ardour environment calling up Zynaddsubfx took relatively long

Calling up the Instrument Bank, again takes a while , " the instrument bank has NO content and the zynadd… window disappears. so, I can´t select an instrument.

Calling up the virtuell keyboard … the zynadd… window disappears

I suspect the problem started with version 6.3. Upgrade to 6.5 did not solve the problem.

I am running opensuse Leap 15.2 (latest version.)

Thanks and have a Covid-free xmas

made an account just to comment on this

definitely a problem with zyn and not ardour, as i tried it in qtractor and this happened too. i was using the official paid binary

installing the free version from kxstudio (the website, not the repo) fixed this issue for me