From time to time, I posted a thread complaining about a strange bug with rapid firing weapons causing sounds to randomly disappear. It was hard to reproduce on different configurations, inconsistent and didn't register on debug builds, making it a nightmare to nail, and I never got around to compiling my own build to track the problem more precisely.
However, last time someone mentioned that it's possible that the sound card has problems handling the amount of sounds that appeared. I dismissed that at first, since the sounds seemed rather short (if they weren't, the result would be unlistenable noise). But then, I took a close look at them.
It turned out those short cracks of gunfire had a lengthy, slowly fading reverb, going on for up to 6 seconds! Now, with two guns firing at 50-100 RPS (I know the tricks to make it work with other FSO limits), the soundcard has to cope with playing up to 1200 sounds at the time, most of them inaudible (though them more typical amount would be about 300 simultaneously played sounds. Still enough to cause problems). No wonder it couldn't cope. Turns out you need to be very careful when choosing gatling gun sounds.