Here's more, from another web forum:
(I have the clock problem described below on my 2017 Impreza Premium hatchback)
Here's the text from the bulletin WTN-74:
"Although the main purpose for this campaign is to address operational concerns involving the rear view camera feature, software is also included in this update for the following other conditions:
1) After switching the vehicle (ACC or IGN) on, the display screen goes black with no audio output and the hard key buttons are illuminated (on solid, or ashing / blinking).
2) Time of day displayed in the MFD (Multi-Function Display) is incorrect and the arrival time displayed in Navigation units is also incorrect.
3) The time in the MFD automatically reverts back to a “default” setting, even after setting the time using “Manual” mode.
4) Audio volume goes to maximum automatically after one click of the volume up button on the steering wheel. In some cases, this condition may also occur without input from the operator. Maximum volume is also displayed on the screen."