I have the same problem. I hear all sounds except the instructor and ATC. I delete all the FSX and reinstalled (about 2h...) FSX and Aceleration pack and the voices returns, but after some hours the voices disappear. When I ready to install the SP2 I read it's only if you don't have Acceleration Pack, it's true?I need a solution, the missions are very difficult with play and read while.Thanks and regards from Barcelona.