Rattling sound acure when moving X or Y axes

When starting a new print on my K1 Max, I first let my machine perform a calibration. During this calibration, the extruder quickly moves around the entire print bed via the X and Y axes to check the bed leveling and the Lidar scan. During these movements, a clear rattling sound can be heard, similar to that of a ratchet. This sound is also present during the first three layers. It is very noticeable because the fans are not yet running. Notably, this sound only occurs when only one of the axes is moving. When the X and Y move together and the extruder moves diagonally, there is no rattling sound. The sound is difficult to locate. It is definitely not the extruder skipping or due to the movement of the Z-axis. I have checked the tension on the drive belts and they are fine. This sound has been present since I bought the machine. I thought it was normal at the time. But I have the impression that it is getting louder.

I have two years of experience with 3D printing with my Ender 3V2, where I have been able to solve every mechanical defect without problems. I am a mechanical technician and have years of experience with troubleshooting. The K1 Max is a more complex machine than the Ender 3V2 and I have a good understanding, but I cannot identify the cause here. Is it in the control of the stepper motors? Can you help me?