Hi, when I hit the start button a knocking sound appears like on the video before the bed moves. I postet the issue on reddit and got belt slipping on the z axis as answer. Indeed it was a bit lose, I tighted not to max just a bit before. But I think it is not the belt because the knocks appears before u can hear the motor moving. I observe the printer since the issue and thats what I notice:
-knocking appears only after hitting print start, not when I manualy move it with the UI
-1 to 3 knocks before beds
moves
-knocks appears not everytime time, I would
say every 3-5 after hitting start
-bed mesh is acceptable for creality
-still good prints
Here a Video of it: https://www.reddit.com/r/crealityk1/s/bFl3bd8xKy