AU Midi Effect plugins from 4.2.4 to 4.3.0

I’ve been trying to figure out for 2 days so far why a plugin is working perfectly as a Midi Effect in Logic when I compile with JUCE 4.2.4 and why it stops working with JUCE 4.3.0 (seeming to block the Midi input even if there is nothing but “return” on the processBlock method).
I’m setting 10.6 as deployment target in both and using the latest version of Xcode.
Help… Does anybody have a clue on this? Anybody can guess what changed between both releases that might be interfering with my plugin? Note: I cannot reproduce this behaviour with the JUCE audio plugin demo when I compile it as a Midi Effect plugin.

Did you try re-scanning the plug-ins in Logic’s Plug-In Manager? Also, have you tried the Arpeggiator example?

Well most plug-ins are not midi effects so it’s not a bad idea to return false as the default.

Do you have the “Plugin is a midi effect plugin” checked in the Projucer? Also make sure that “Plugin AU Main Type” is empty in the Projucer. How is your plug-in listed in auval (try auval -a and search for your plug-in code triplet - for example - the Arpeggiator example has aumi Arpg ROLI. Then do auval -v aumi Arpg ROLI to validate your plug-in. Your plug-in should have the aumi effect type code otherwise it won’t function correctly!)?

If the Arpeggiator example works, then the only thing for you to do, is to painstakingly go through any differences until the Arpeggiator matches your code.