I had a quick look into this. I think the assertions are valid - these plugins are requesting an input bus that should be active by default, but should have no channels. This seems a bit weird to me… It’s not clear to me whether this is allowed under the VST3 spec (it passes the “official” validator, so it seem to be OK), but I’m not sure why an empty, active bus would ever be desirable.
I think these assertions should stay. It’s useful to know that the plugin is doing something a bit unusual when testing a custom VST3 in the AudioPluginHost.
The other assertion I see is a request from the plugin to open the editor. We don’t have a way of surfacing this request through the JUCE API at the moment, and I’m less sure that this assertion is valuable, so perhaps we should remove this one.
I don’t know enough about the VST3 specs in this case, it’s just strange to me that a plugin that loads correctly in most/all hosts (AFAIK) is asserting.
Do you think this is a problem I should be reporting to Waves?
It definitely seems a bit strange. If nothing else, it’d be interesting to hear whether this is intentional, and why an empty bus is preferable to a disabled bus in that case.