Some multibus issues

We are moving our host over to the “new” multibus structure. got most of it figured out, and are testing different plugins. and comparing our results to the Plugin Host Demo.
This has made be aware of some issues that are also present in the host demo, and therefore I pass them on to the Juce team
The issue:

The plugin INA GRM Spaces:
And a couple of other plugins, also some Juce based,like this free-one:

show strange behaviour.
If loaded they look like they have multiple busses/channels but internally they only see 2.
So the “gain” plugin shows up like 4 channels but only applies it’s gain to the first 2.
The spaces plugin shows up with 32 channels but, when you go to “I/O setup” in the plugin to route audio it “thinks” that it is only loaded as stereo.

I didn’t test the spaces plug-in but the gain plug-in you shared seems to be working fine. Internally it’s reporting the correct number of buses and channels:

Hi Fabian, thank you for looking at this.
When i tried, it also looked like it should work, the plugin comes up with the right number of busses and channels, but it only processes two, (adds the gain value)
I also talked to the Spaces vendor, that plugin is also Juce based. (maybe they are reading this)
They told me that the issue was because they had not migrated to the multibus api, but where relying on the getSpeakerArrangement function, and that reports stereo.
So it seems to be an issue with older juce plugins in new juce hosts. does this make sense?