the game publisher will need to fix this
That's what I figured but do they read the reports here or do we have to report external issues directly to third-party developers?
Problem is solved when setting SLD_AUDIODRIVER env var to "alsa". Not sur why it isn't needed when using libSDL from the system.
Please send the issue directly to the third-party developers.
Nothing extracted yet.
Already reported the problem on Steam but I suppose here is a better place : http://steamcommunity.com/app/221410/discussions/1/882966056886209441/
The Azalia chipset is a sound chip that is (AFAIK) beginning to be widely-used as replacement for AC97 integrated chips on motherboards. It has issues on Linux/PulseAudio with some softwares and produce bad sound (cracks, buzzs, echo, saturation and so).
This happens with Darwinia and Uplink on Steam Linux. Probably with other Introversion games (Defcon and Multiwinia) but they're not currently installable.
As I owned these games before having them on Steam, I could check is the issue was present in non-Steam versions of these games. It is not.
I've tracked the origin of the issue to the SDL library that is embedded with the games (libSDL-1.2.so.0 in SteamApps/common/Darwinia/lib, lib64 and similar paths for Uplink). When removing the lib, the sound of the Steam version is fine, as it then uses the lib installed system-wide from the Ubuntu repositories.
So I guess that the problem comes from the fact that the embedded libs are too old or faulty and would probably be fixed by putting an up to date version of libSDL-1.2.so.0 in the games libs dirs (or remove them completely but users would then have to have libSDL installed from the repos).