Here is an old (2015) fix for similar problem.
Don’t know if I should try install this, because its from 2015.
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Hello again,
Today we have released the new Audio Unit patch.
The patch fixes issues that you may encounter when running our VST instruments on Mac OS X versions 10.10.5 (and earlier) in AU hosts. Please make sure that the latest version of the plug-ins is installed before installing the patch.
Please visit the support download page for your VSTi product to download the patch, or follow the link bellow:
http://download.steinberg.net/downloads … er_mac.dmg
Best regards,
GN
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