Hey guys, I got a response to my ticket.
Dear Bambu Lab Customer,
Thank you for contacting us and providing the information.
Hello, after investigation, we have confirmed that the issue originates from the motor. When the motor is stationary, a current is injected to maintain its locked position, which can produce this sound. We are currently optimizing the firmware to address this phenomenon. The sound does not affect print quality and does not occur during the printing process. Please await our upcoming firmware version updates, as future releases will aim to minimize this sound issue.
If you have any further questions or require additional assistance, please don’t hesitate to contact our customer support team. We are here to help.
Best regards,
Bambu Lab Customer Support
It seems that the issue will be improved in the next firmware update. I’m glad it’s not a hardware issue 