Scroll wheel randomly changes it's scrolling speed, smoothness, line by line is more like 3 to 5 lines, etc. It is getting annoying. It has been an issue for a while now many others report these issues but seem like no work on it to fix it. I look at other's report and could vote for all of them because the randomness of the scroll fits all reports. Seems weird that scroll is an issue because Logitech has been making mice for decades.