Enmoku: The game doesn't like AMD dual-cores at least (something to do with the RDTSC bug). Forcing the game to run on single core helps a bunch (Win95/98 compat mode does this, since Win9x doesn't support more than single-CPU).
Hmmmm... I'm on an AMD dual-core, Win7 x64 and experienced the hyperfast, sound-skipping on first run. Set compatibility to Win98/ME and, yes, the sound improved as the general speed of the game felt much more like "human experience" realm. However, most text such as subtitles, etc. were rendered at teeny-tiny size (like 2-3 pixels tall).
A better solution, at least for folks like me with AMD dual-core, is to set the process affinity to a single core. Once I did this, I was able to run without any compatibility mode being set and all was well.
NOTE: Since the GOG exe seems to run in admin mode, you'll need to start the game, bring up the Task Manager, click the "Show processes for all users" button to get the Task Manager into Admin mode, too, THEN select the Perimeter.exe process and set its affinity to single core.
BEST SOLUTION: Use the free ICEAffinity utility to do this tweak programmatically at launch. Grab it here:
http://www.ice-graphics.com/ICEAffinity/IndexE.html. I simply put a copy of ICEAffinity.exe in my Perimeter game directory and tweaked the GOG desktop icon to call it like this:
X:\PathToGames\Perimeter\ICEAffinity.exe 1 "X:\PathToGames\Perimeter\Perimeter.exe"
Finally, remember to set the tweaked desktop icon to 'Run as Admin' as ICEAffinity will need elevation to itself adjust an exe that runs as admin.
