Thank you for the additional insights. Muting the master channel group shouldn’t dismantle the output, as mixerSuspend does, but while investigating this I did find a race condition where a crash can sometimes occur if a device is connected, and then disconnected while the new device is starting. This might explain the July crashed that didn’t involve mixerSuspend.
I’ve uploaded a non-QA-approved build containing this fix to your FMOD profile, and it would be great to hear if you can still reproduce any of these issues.
We recommend never shipping with non-QA-approved approved builds, so please ensure you update to 2.03.16 when it becomes available.