Im new to this site and yes I have experienced that as well. I have windows vista home premium desktop. My sound and graphics look excellent during flight, but whenever I exit a campaign mission it freezes 90% of time right after I press the "esp" key on the keyboard. The whole entire window minimizes to the bottom tool bar of my desktop. Then I click on it to bring it back to full screen to find there is no sound. Complete sound drop out, and sometimes that carries into the next mission unless I restart the sim. After saving everything of course. Sucks, but I still get the job done. Could be worse. Most current update had been installed as well.