Remove Sandboxing

Solution 1:

On Xcode 11, you can turn off Sandboxing by removing it from the Signing & Capabilities tab:

Solution 2:

If I understand what you are asking correctly, you'll need to remove the entitlements.plist from your project and make sure that the Summary view of your target in Xcode has sandboxing turned off:

Solution 3:

As Derek Wade pointed out, you can make an App like GarageBand X (which behaves obnoxiously with third party plugins like Amplitube due to Sandboxing) NOT run in a sandbox by editing the binary itself with a HEX editor like HexFiend. Look for:

<key>com.apple.security.app-sandbox</key>

Immediately following that bit you'll see the true tag, which as suggested I switched to 'fals' (no extra bytes) and now GarageBand will happily interact with third party VST plugins. Huzzah.