My mouse scrolling does seem to malfunction in the editor.
First I though my mouse scroll button is broken but I tested it in other applications and it works fine.
Only in PyCharm, the scrolling seems to be undersampled (only few scrolls out of tens is catched).
I am using Microsoft Sculpt Ergonomic Mouse http://www.microsoft.com/hardware/en-gb/p/sculpt-ergonomic-mouse
Is there a solution to this problem?