It’s great that the older Tomb Raider games are still so popular that Steam and GOG have put out their own versions. However, the one thing missing from these games is the wonderful music soundtrack. I searched for a long time and tried various fixes before I came across this on the Steam website:
Make sure you have a clean install of the Steam/GOG version first. Get the latest version [github.com] – click “Download Tomb Raider Automated Fix”
Run the file to install.
Once complete, launch the game on Steam and select “Tomb Raider I” or “Unfinished Business” from the launcher.
If the launcher won’t open and your PC is severely outdated, then you need .NET Framework