After 3000 hrs, the original extruder on the X1C finally gave out. RIP
Prints started to get all wonky about a week ago. I couldn't figure out the problem. Changed the nozzle, tighten the belts, lubed the z screws, and cleaned the carbon fiber rods. Disassembled the extruder and I didn't see any clogging, but when I disassembled the hall sensor, I noticed a lot of wear. Then I found a piece of metal inside the extruder that I suspect broke off from the hall sensor somehow. A new extruder arrived yesterday and the X1C is printing like a champ again.
I noticed that towards the last couple of hundred hours it started to clog/jam a lot more. I thought the gears might be wearing but it looked ok upon visual inspection. I wonder it's an early warning sign. I only print PLA and PLA+ so nothing abrasive.