What makes that sound when UM2 are retracting

[TMicke 23]

When the UM2+ retracts, there is a sound (a double beep), change speed of retractions and the pitch changes.

 

What makes that sound, and can it be stopped or at least reduced?

 

*edit

Bondtech’s ultimaker 2 kit contains a vibration isolation between motor and chassis and the gearbox itself has vibration isolation foam.

 

https://www.bondtech.se/en/product/qr-ultimaker-2-kit/

I guess this answers my question.

 

If anyone who has one of these installed can confirm I would appreciate it.

Thanks

Edited August 1, 2019 by TMicke