Question

Can't see any mention of iTwo firmware changes in those

In the absence of documentation I followed the UC instruction "Please install new firmware!" now I can't put the Mac Pro to sleep

iTwo now starts blinking when the machine is put to sleep mode then wakes up the Mac again. Also audible glitches when moving between apps.

Do you know how to roll back the driver?

Answer 1

The iTwo uses the Apple Class USB Audio Driver. This may be more of an issue for Apple than for PreSonus. 

The iTwo does feature embedded firmware that is updated using Universal Control. 

You can find older versions of UC 2.0 and 1.8 in the legacy downloads section which have older firmware versions that you can force if you think you want to try that. 

Do NOT load AudioBox VSL 1.3 software as the firmware update in that version will not recover if there is an issue. The iTwo will exhibit all lights on if the update fails. To recover from this, install UC 1.8 or higher and run the firmware update to fix the frozen state.