Hofmann Lift MTF 3000 stops while lifting and makes noises

Hello, I have a Hofmann MTF 3000 lifting platform here. Strange is, whether loaded or not, the secondary side runs slower than the primary side. This leads to the lifting platform stopping 5x between below and above to compensate for it. Now I had noises, which I removed by having cleaned everything and having cleaned both spindles and also completely smeared the lifting sleds. The noise is now gone, also the safety nuts are still top and at the If I take off the covers of the primary spindle I see a wheel in which the balancing train is suspended and the wheel moves exactly when the wheel is stopped. I don’t have any differences in what I have, so I measure e.g. when the lifting platform is semi-propelled. Here I have the same distance from floor with scale to the bottom of the support arms. Now my question is this, despite the synchronous running, that one side sticks and waits until the other I guess they’re okay, right? Answer would be super nice.