I just finished replacing the extruder motor in my A1. It was not too difficult just tedious, however when I tried to load filament I got a vibration noise from the new motor and it was not turning. To check properly I took the motor out of the housing it is in and connected it up outside the printer, I then hit the extrude button which lets you try it even when nozzle is not heated and the motor sat on my desk vibrating and not turning at all. Can anyone suggest what the issue might be as I am hoping I did not receive a faulty motor from Bambu. I have a video of it vibrating but do not know how to post that here.