I'm actually having the exact same problem. During missions, when the avatar of pilots show up in the top right-hand corner, the animation occurs but with the audio noticeably absent.

Interestingly, I'm also using the digital download version.

If anyone know a solution to this issue I (and I'm sure infamous jeff) will greatly appreciate it.

Thanks for the feedback Guitarlord and Tremerid (especially Tremerid).

It turns out the digital download version doesn't even have the Tachyon.CFG file (not to be confused with your save game config files)!

Very poor quality control on NovaLogics part. Not only that but their tech support put me on hold for 50 minutes and never replied to my email. Very poor customer service as well. I doubt I'll ever buy directly from them again.

But regardless, Tremerid's solution works perfectly (although the game seems to be crashing with a higher degree of regularity now, but at least it's playable). The only (other!) ridiculous thing was tracking down the demo, as most of the files seems to be dead links or links to "try media" version - i.e. the inept digital version we all seem to have.

But at the bottom of the sixth page of googling "download tachyon the fringe demo" I found this Spanish website:

http://superdownloads.uol.com.br/download/110/tachyon-the-fringe/reviews-usuarios.html

For those who are having trouble finding the demo (for the much coveted config file) navigate to that link and click on the orange button on the right.

Also, it's not just the right hand pilot icon sounds that were missing but a whole bunch of wingman chatter and mission diagnosis, etc. So once you guys fix your sound problem, I recommend starting a new game so you don't miss out on most of the experience!

Hope that helps, and thanks again Tremerid.