I noticed a few days after upgrading to Windows 7 64-bit (final) that my system sound levels would be reduced a lot (barely audible at times) when I would exit FSX after a 15-20 minute flight. I am using on-board Realtek audio and trying several driver versions intended for Windows 7 64-bit made no difference. I eventually determined that this happened ONLY when I had heard some ATC communications with AI aircraft and that the length of flight had nothing to do with it. If I detuned COM1 so that I did not hear any ATC communications, system sound levels remained unchanged on exit from the sim. I also determined that restarting the Windows Audio service would restore system sounds to their normal levels. There has been no detectable change to the volume level setting for system sounds.Has anyone else experienced this? Any suggestions for a possible fix?Rick

I noticed a few days after upgrading to Windows 7 64-bit (final) that my system sound levels would be reduced a lot (barely audible at times) when I would exit FSX after a 15-20 minute flight. I am using on-board Realtek audio and trying several driver versions intended for Windows 7 64-bit made no difference. I eventually determined that this happened ONLY when I had heard some ATC communications with AI aircraft and that the length of flight had nothing to do with it. If I detuned COM1 so that I did not hear any ATC communications, system sound levels remained unchanged on exit from the sim. I also determined that restarting the Windows Audio service would restore system sounds to their normal levels. There has been no detectable change to the volume level setting for system sounds.Has anyone else experienced this? Any suggestions for a possible fix?Rick

I have noticed this also... not sure of the cause..

Well, Jason, I think I may have found the "fix". It appears that Windows 7 thinks we are communicating (on the phone), which I suppose we are in a way since this behaviour seems to be triggered by ATC voice chatter. In the Windows Control Panel - Sound applet, there is a new tab "Communications" with some settings options. Mine was set to reduce sound levels by 80% when Windows detected communications. I set it to Do Nothing and an initial test in FSX was successful. System sound levels were retained after exiting FSX.Of course, something else may have "fixed" things and I just noticed it now. YMMV.Rick