Hi there,
I'm having real trouble with the dialogue in game. The voiceover generally only ever gets through the first of its line before it skips to the next. This means the subtitles pass very quickly and it is often really difficult to read them before they vanish.
Is anyone else having this problem?

System specifications? You might try running DXdiag and turning down the audio acceleration. Also, I think I saw this problem on the codemasters perimeter forum, so try looking there. Its hidden under the back catalog category.

The game seems to be running too fast; the clock in the top corner is ticking up way too fast!

Try hitting the turbo button on the front of your computer.
Ok, just kidding, but seriously I doubt the problem has anything do do with your audio subsystem - try forcing v sync in your graphics panel, and of course make sure your graphics drivers are up to date.
The problem you are describing is very unusual for a modern game; it sounds like there is something seriously wrong with your drivers.
I know blaming your display drivers for symptoms presenting from your sound card seems counter-intuitive, but try it.

I'm guessing that the game is simply running too fast. I'm running some dual core thing, and I suspect that it just chews the data for this game too fast. I can remember the same kind of problem happening for Warcraft II last time i tried to play it on a Pentium III. It scrolled too fast, and was generally sped up weirdly.

Was a solution found for this? I'm having this problem on my laptop too, although on my work comp it behaves fine. I haven't messed around with it enough yet.
Edit: Never mind, I got it working. I ran it in Win 98 compatibility mode, that's sorted it out. It run smoother now as well.

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.