[ubuntu] usb mouse drags file at some point without releasing

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http://ubuntuforums.org – Hello! My Trust usb mouse does sometimes strange things w/ Ubuntu: * sometimes left click is suddenly disabled, I keep clicking and nothing happens, then I must use touchpad in order to click * sometimes it decides to drag a file (a video, for instance) along the screen without giving me the possibility to release it! I have to unplug the mouse and plug it back What should I do? Thanks, Mario Alberto OS: Ubuntu 9.10 PC: Sony Vaio SZ61-XN/C (Hardware)