This is a very undocumented problem, I've been using google to no avail. While performing preflight on the NGX, I experienced sudden loss of audio. Some things to keep in mind: I run all FSX sounds through my default creative soundblaster sound card to my speakers, and FS2 Crew through my USB headphones. I have up-to-date drivers and have had no significant software changes, and I have no viruses, spyware, malware. This has happened 4 times in the past 2 days. Basically this is what happens: The sound suddenly cuts out of my speakers, but FS2 Crew continues working. Audio was not on mute, the fsx sound menu had primary set to default device and voice set to headphones. I pressed mute on and off, no response. Sim was not on pause either. I minimized FSX, and my first step to see audio was working was to play a YouTube video. The video would not play audio, and the video itself was playing frame by frame. The default device it still detectable in device manager. When I reboot, everything goes back to normal.

 

Has anyone experienced this problem, and if so, what is a solution? Thanks!

The first step in troubleshooting is to bring the program back to basics and see if the problem remains.  This would mean disabling the add-ons you're using.  If the plane's audio works fine, then add back in the various add-ons to see if you can identify the one having an issue with FSX audio.

I had the problem occur outside of FSX today. Should I reinstall or roll-back my sound card driver?

have you tried pressing  q  twice

Yes indeed. Is it possible that this may be sound-card failure? I deleted all drivers, then reinstalled them, and the problem happend again within 10 minutes. If I unplug speaker chord from the sound card and then into the mother board sound, then set the mother board on board audio as default, while the is problem is occurring, I regain sound.

It can't be a complete failure because occasionally sound works, and quite well up to a point. It's almost right on the dot failure around 15-20 mins if play time. If it matters, this is a Creative Soundblaster X-Fi Fatal1ty Titanium champion card. Are there known issues with X-Fi cards?

I'm guessing the DSP (digital signal processor) chip on the sound card has a thermal short that kicks-in after it's been working for a bit and the chip warms up.  Either that or a cold solder joint.  Regardless, sounds like it's time to try a new sound card.

I agree with Larry - it could also be a cable or jack problem.