Recently my Logitech MX700 mouse

Question

Recently my Logitech MX700 mouse seems to be misbehaving and I can't figure out if it's the mouse or software.There are a couple of symptoms. First: try to highlight a line or two and the highlight turns off before you get the entire block highlighted. This happens over and over again.Second: click on the top of a window to highlight it or drag it and about 50% of the time it's exactly like clicking on the full screen button.