Precision 3530, middle Pointing-Stick button doesn't work

I've configured the middle pointing-stick button to enable scrolling, but nothing happens when I hold it down and push the pointing stick. I noticed that if I double click and hold the middle button, then it it possible to scroll. Mouse icon does not change and it is not visible that the scrolling mode is active. The sensitivity is very high and it is very uncomfortable to use. I have experience with Lenovo pointer sticks. It seems to me that it might be a software problem (drivers). I updated all drivers using the "Dell command update" tool. I tried to downgrade the drivers. Nothing helped. The ePSA diagnostics did not show any errors. We have several laptops in our office and all of them have the same problem. Do you have any idea what could help? Thank you.