This issue has been logged with our development team in hopes that it will be addressed in a future update. Should the issue be addressed in an update, you will see it in the release notes of that update.
As a workaround, you can create an aggregate device on your Mac that incorporates your built-in output with your built-in microphone. Here is a link from Apple that explains how to create an aggregate device.
Once you have created the aggregate device in the Audio MIDI Setup, the first time that you launch Studio One it will crash. The second time that you launch Studio One, you can tell the program not to use the built-in output, and it will automatically switch to the aggregate device. Please let tech support know if you have any problems.