Dash/entertainment goes off

Nissan Altima SL 20022. While driving, this morning dashboard and entertainment system lost power. Stopped the car a few minutes later and restarted it, and it was good again. Car still drives ok, air still blowing during the malfunction.

This evening grocery’s on passenger seat, passenger seatbelt warning starts going off. Grocery’s must have shifted enough to set it off I guess. A couple of minutes later, warning still going off, the dashboard cluster went and entertainment system go out again. But this time they came back several seconds later.

Battery is 3mo old, looks clean, 14V idling, 12.6V off. Sitting in driveway car freshly turned on and not experiencing the problem I can toggle lights on/off all lights working, high beem and hazards working. Also checked the 2 fuse boxes under the hood and under the steering wheel, not got as far as testing any fuses but all connections seem good. Seems kinda odd to be a fuse issue though if it starts working again.

What could it be?