ASA578 DePress problem

Listening to KSEA tower, Alaska flight 578 to denver is returning to Seattle after some sort of a minor pressurization problem. no masks deployed, no emergency delcared but imeediate turnaround requested.
You can see the interesting figure-eight they’re doing to turn around.

flightaware.com/live/flight/ASA578

Some slight ear injuries:
kgw.com/sharedcontent/APStor … E3VG3.html

Sounds a bit sudden, I’ve been on a DC-9 which wouldn’t pressurize or rather blew the air out the tail door seal every time we got above FL10; it was uncomfortable but not injurious.