This is one of those off-topic blog posts that I eventually write, but I spent significant time trying to figure out why my Logitech G700s mouse doesn't move in a straight line and I think it would be worth it.
I couldn't find solutions for this on the web. My problem is simple - I move the mouse and it doesn't go smooth in a straight line. It jumps sporadically across the movement vector at about 0.5-1cm off its course, making it impossible to use for games or anything for that matter. I can't really demonstrate it easily, but it was bad.
I got initially put off in the wrong direction - drivers. I did all kinds of installs and uninstalls, both native windows and Logitec. I played with the pointer speed settings both in Windows devices and in the Logitech mouse drive software. None solved my problem.
I even tried different mouse pads.
The issue at hand is that it is just dirty - the laser heads have very tiny dust particles that are very difficult to see. I tried blowing them off, but I'm not a good blower.
My fix is easy - I stuck an almost dried out wet wipe tissue into the laser hole and rotated it a few times. The laser heads we're visibly cleaner.
Now it works like brand new. This is one of the most smoothest mice I have owned and it is fantastic.