2000 Mazda 626 5th gear popping out on acceleration

Hey y’all, just picked up a 2000 Mazda 626 with a manual 5 speed the other day. Car was working fine for a day and a half until it started popping out of 5th gear under acceleration on the freeway. Previous owner had the 5th gear selector fork replaced recently (as well as clutch and engine mounts). Does this sound like a synchro ring going out? Really hoping I don’t have to pull the tranny