I only hear the music! I've tried different solutions all day. It starts that the sound lags and starts in a loop for about 5-10 seconds then it goes silence and i can no longer hear footsteps, npc voices, gun shot etc.
I bought Fallout new vegas on steam sales and i installed it a couple of hours ago, but i discovered that the sound effects disappears after 5-40 minutes of gaming. I'm going mental, i can't solve the problem with fallout new vegas!