I'm the Co-Leader of the FringeSpace project at www.fringespace.org... I've been helping players for about 3 years now.

To cut to the heart of the matter, I think Novalogic broke something in making the game a downloadable version and it seems to be across several pay2download sites.

I've heard it first hand from no less than 3 people already about the audio and graphics looking terrible in the downloadable version.

The reason multiplayer doesn't work is that NL moved the servers 2x, and lost their server maps in the process. So they could no longer host games. Why they didn't allow player hosted games... not sure but they may not have known which files to edit.

There's a fan made utility that can fix the multiplayer issues and allow player hosted games (there's a server up 24/7) and can add mods if you wish as well.

Now specifically on the audio, you might try the Tachyon Service Bay fix and see if that helps. If not I do have the original demo available.

However I would caution about the old demo, because it was several times more buggy than the retail copy was at release.

I wouldn't expect any real support from NL. They've largely pushed Tachyon under the rug and you've never been able to be a part of the Novaworld forums using Tach CD keys. We've had to send 3-4 emails in the past to get a response.

There's a good amount of history involved in why Tach is as broken as it is. Largely it can be surmised as NL kicked it out the door too fast, and it was the developer's precious child that they were not allowed to finish properly. Not long after most of the dev's split from NL so I doubt there's many people with knowledge of Tach's inner workings even left at NL.

But drop the community a line at the FringeSpace site.
Might be able to narrow all these little bugs down.