Vcore 3.1 500, stops extruding mid print

For the past week I've been having this issue where my printer stops extruding mid print, at random heights. No clogs, just my pla being worn so the teeth don't grip. I think it's having resistance issues in the routing, and putting on a 3kg roll made it even worse. I have changed the routing, put on a 3kg, 1kg and 200g spools, took the lid off, took the door off, nothing changed, still stopping at random points. Is there anything I'm missing here? Could it be the extruder that is at fault? I took that apart and it looked and worked fine and clean. It's been driving me up the walls and I don't know where to look anymore..