VST3: incorrect I/O port count, occasional missing MIDI input

[x42]

When using Helm VST3 on MacOS the plugin sometimes shows up without a MIDI input, and the number of audio-outputs also varies, usually mono-out only.

Tested with Reaper and Ardour-nightly builds.

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It smells like an uninitialized variable, but I have not yet been able to track it down. Perhaps the issue is already fixed in upstream JUCE's VST3 support.

HelmPlugin uses the default JUCE AudioProcessor c'tor, that starts with disabled I/Os

AudioProcessor (BusesProperties().withInput  ("Input",  AudioChannelSet::stereo(), false)
                                 .withOutput ("Output", AudioChannelSet::stereo(), false)) 

So it's odd that it comes up with any output at all..

[DavidsonAudioMulti]

It comes up as mono for me also.. Reaper Mac and PC win 7 & 10..

[DavidsonAudioMulti]

Odd thing is that it performs as stereo anyways..

[fgimian]

I can confirm that VST3 is mono here on Cubase 9.5.20 on Windows 10, VST2 is stereo as expected.