slowdown on windows not in linux

hello, my problem is this. Start any game. frame rate and audio are good. I close the game, restart dolphin and the previous game but at this point the fps drops dramatically and there are problems of synchro audio.
i use the following settings: default + ogl (DirectX11 same problem)
dsp on thread On + Vbeam speed hack actived (depending on game).
I did another test I tried dolphin x64 3.5-1670 also on linux mint 14, same settings of the Windows version there is no problem on linux