Assertion error line 1843

[2eleven music film]

Hi Avid Pro Audio Community,
I'm new here and wonder if you can help me getting started ProTools 2021.6 on an iMac 27, Intel i9 with a SPL Crimson 3 Audio Interface:
When I start Pro Tools under Setup/Hardware there are no Peripherals listed. When selecting "Playback Engine" the following alert pops up:

Could not complete the Playback Engine command because Assertion in "/Users/autobld/gitlabci/PT/release/2021/r2/ProTools/DFW/Views/UMenu.MacOS.mm", line 1843.

I've checked already the Mac OS System PReferences. The SPL Crimson is registered. It is also shown at Audio-MIDI-Setup and activated under Pro Tools Aggregate I/O.
What else can I do, to solve the problem?

Thanks in advance for you advices.

[defra]

Same situation here, getting nuts. Any help appreciated.

[defra]

Just downloaded v.2021.7, that issue solved, but with this one I have a problem (cannot change plug-ins) if I Organize Plug-In Menus by Category and manufacturer, only works with 'manufacturer' only; this could be because i trashed plug-ins Settings previously.

[defra]

Just downloaded v.2021.7, that issue solved, but with this one I cannot change plug-ins if I Organize Plug-In Menus by Category and Manufacturer, only works with 'manufacturer' only; this could be because i trashed plug-ins Settings previously.