AUv3 problem in GarageBand and Logic Pro X

Recenlty we released Tonebridge for macOS (https://itunes.apple.com/us/app/tonebridge-guitar-effects/id1263858588?mt=12) and added Audio Unit V3 effect for it. We faced a problem—the Tonebridge Audio Unit is available from the list of Audio Units (see screenshot), but when you try to add it to any track, it doesn't work and shows a red exclamation mark instead (see screenshot).

The problem appears both in GarageBand (10.2.0) and in Logic Pro (10.3.2). We use the most up-to-date versions of the apps, and we use macOS High Sierra (10.13). We developed our Audio Unit according to the official Audio Unit sample for developers called FilterDemo (https://developer.apple.com/library/content/samplecode/AudioUnitV3Example/Introd uction/Intro.html). When we try to run it in GarageBand or Logic, the same problem appears.

We found a solution for Logic Pro. To fix it, you should go to Logic Pro X/Preferences/Plug-in Manager, find the Tonebridge Audio Unit, turn the “AUv3 Mode” tick on (see screenshot), and reload Logic Pro. After that the Audio Unit works correctly. More to say, if user has GarageBand installed, the solution fixes the problem in GarageBand too.

Unfortunately, there's no option to run the Plug-in Manager in GarageBand, so we needed to find another solution for users who don't have Logic on their Macs. We found that when you turn the “AUv3 Mode” on, the 61756678-66317452-55475442.tagset file changes in the ~/Music/Audio Music Apps/Databases/Tags directory.

Here's what is added to the file:

<dict>

  <key>outofprocess</key>

  <string>tag</string>

</dict>

As a temporary solution, we give our users the same solutions we mentioned above, but this is a bad user experience. It would be ideal if the “AUv3” tick was turned on by default for our Audio Unit, so users wouldn't do any additional steps to make it work. So, we would like to know if there's any possibility to tell a host app from an Audio Unit that the Audio Unit should be run “outofprocess”? Maybe there's a flag somewhere inside the “NSExtensionAttributes” section of the “info.plist” file that we didn't find? Thanks in advance.