Never happened to me while I was docked, but only outside. In the past week or so it happened many times and I've noticed that when I'm mining, my fluct goes from 4-10ms. In some past cap fights the mouse lagged heavily, it gotten to a point where I wasn't able to do anything but wait for it to pass, after doing /ping I've noticed 30% lag and all other crap while my internet was perfectly fine.