Not sure if anyone else has had this (just did a quick search and only found this from 4yrs ago).
Our 5.5yr old/78k miles XC90 suffered it this week.
Problems are related to the AUX battery, I think. But may also be the way the AUX and main battery are used.
There's a Volvo technical bulletin that covers similar (if not identical to ours) symptoms - TJ34142
Indie has serviced the car....tried a reset (disconnecting the battery for 15+mins) but was still doing it. So AUX battery replaced (£115)....they've tested it and declared it OK, but said to run it for a bit and if the fault returns, we can look further.
Thought it might be worth posting up here as I suspect a lot of cars will be coming to this age/mileage now
