I am not playing intense games when I leave it on, for those I might turn it off (crashes in new and old games alike). Easy things that came out years ago, uses akin to 20% of my resources, no reason to shut things down.
I will try your suggestion next time I start a game I have problems with Lupin.
Edit: That solved it, now I can keep it up in the background along with everything else. (Currently 10 things up and a few in tray. ^^)