[ubuntu] USB mouse shuts down when on battery power

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http://ubuntuforums.org – Dear friends: I have learned a lot on these forums, thanks to all your postings. I have a Sony Vaio VPCSA laptop with 8-gigs of RAM. I installed 64-bit Ubuntu 12.04 LTS, and it is working extremly well. My only complaint is that when I am on battery power, I can plug in my USB mouse (I do not like touchpads very much!) in to the port, and it will begin working just fine, and continue to work as long as I never stop moving it. But the moment I hold still, the mouse shuts off, and no longer works unless I unplug it from the USB port, or plug in the laptop's charger. This does not happe (Hardware)