Summary: People having same issue with this particular mouse and its cable. Do not buy it. In my particular case, after 3-4 months it died. Where the cable meets the mouse its a very weak spot that with a little tug and eventual bending happening in normal usage can turn your expensive mouse to nothing. I mean, this spot its not even broken or badly beny. Its a weak piece and terrible design. Look for other reviews and you'll see its a common problem. Avoid this product.
Summary: I put a lot of faith into Logitech because of their durable $20 mice that I have gotten so much good use out of. I decided to spring for this gaming mouse and regret it. First, my mouse sensitivity kept changing and I would have to go into the software to readjust it. Then, after a year of use it started doing this thing where it would stop working, I would hear the disconnect sound from Windows, followed by it working again.
Summary: This was not an inexpensive Mouse.. We were shocked that the USB wires where they enter the mouse had broken in about 2 weeks. The mouse was intermittent in use. If you wiggled the USB cable near the mouse you could see the mouse work and stop. I think Logitech used too thin a cable .
Summary: This model and probably other models of Logitech mice have this major issue with its wheel. Eventually it will stop working and even worse malfunction and seems like Logitech offers no solution to this matter. I should've googled about this mouse before I purchase. Now that I google "G400 wheel problem" I see tons of other people having same issue as me.
Good ergonomics. Bad design particularly the cable.
Chris Miller, Amazon
2 September 2013
Summary: Logitech mice have always been my fallback mouse. I've tried other brands and haven't had the same experience with them as I have with Logitech. Until now. This mouse has died on me in less than one year. It started disconnecting. All the time. I thought it was a problem with the system more than the mouse. Systems always seem to go wonky at times. It persisted until today. About a week ago I came across thread with people having the same issue.
Summary: This is my second mouse from logitech with the same issue; random disconnects. I can be hard on a mouse. I have a home office where I do graphic design all day and then at night I game a few nights a week. I usually get a year or two from a mouse and I think that's reasonable. However, I've been using my logitech now for 3 months and like the last logitech before it there are random disconnect issues. I'm certain it's the cable flexing near the mouse that's causing it.
Summary: I got this mouse a while ago, and for a time it worked out great. However, due to the fact that the idiot designers neglected to put flex support or anything at the ends of the wires, you WILL get fraying and eventual breakage at both ends. Get a mouse made by somebody who knows basic design.
Summary: After only about 6 months of use, the mouse now randomly disconnects and reconnects every few minutes for several seconds, which is extremely frustrating and disruptive of whatever you are doing. Looking around online this seems to be a common issue with this mouse and there does not seem to be any definite fix for it. It is disappointing that the quality of logitech products has fallen so much in the past few years.
Summary: Despite having to install special drivers, this mouse was decent for about a year. Then it began cutting in and out intermittently. I thought I had a lemon, so I contacted Logitech support. They weren't interested in fixing it, despite going back and forth with me with silly 'reinstall driver' fixes. Oh well. Then I Googled the issue. Turns out TONS of folks with G400s get the same intermittent cut out issues after a year.