Stepper Motor make strange noises

[Khayrisill]

Good Morning everybody,

For a few days one of my stepper motor (X tower) make some strange noise. It's not all the time, but when it moves especially over small distances. Machine off, I can hear these little ''crack'' or ''click" by moving manually.
I removed the belt to try without the 2 bearing and i can feel in the motor some tiny tiny tiny vibrations amplified by the tension when the belt are in place. I don't know if its normal but i feel nothing in the other tower.
I didn't notice any special things when the printer work. These noises can especially be heard during small infill when the head move on small distance.

Someone has already heard this with the stepper motor ?

thx