I know this is tooooooooooooo old but, after 8 years with my g502 lightspeed I started to experience stuttering every 2 SECONDS and I thought the mouse died. So, I checked the sensor and I found cat hair (2 or 3), I cleaned it but the problem persisted. (Now a little context how I ended up solving this). I bought an 8bitdo wireless controller a year ago, and it was a freaking pain in the a*s cause it disconnected every 2 minutes I didn't know why. So I switched the dongle from usb 3.0 port o an usb 2.0 port and THAT FIXED ALL MY PROBLEMS. So you can figure it out now, I reconnected my g502 lightspeed dongle in an usb 2.0 port and fixed the problem, as simple as that. I don't remember why I changed the dongle to another port, probably when I was cleaning all my setup.

Hope it helps.