I was just playing a game of Dota2 using my GX850 mouse on a Razer Goliathus mousepad when suddenly the cursor moved very slowly even when I dragged the mouse across the mousepad. All the buttons on the mouse still work fine.
I immediately went to restart my computer hoping the problem would fix itself but sadly, it didn't.
After doing some research and testing, I found that the mouse only stopped working when it's on a non-reflective surface.
I tried it on a several glossy surfaces and it seems to work fine.
(This happened to both my GX850 mouses. The first mouse still works on non-reflective surface but it responds very badly.)
What confuses me is why does it suddenly stopped working on non-reflective surfaces? It used to work just fine on the Goliathus. I've been using it for several months now.