loony,
First the basics, make sure you have the latest sound card and video card drivers. There's other threads that can help you on that subject, but the main issue is to make sure you uninstall the old drivers before you update with the new ones.
From other threads here there are two things to try right away:
1) Make sure your Sound Card is at 3/4 acceleration. Go to: Start/Run, type in dxdiag, chose the sound tab, set slider to 3/4.
If that doesn't cure it:
2) Change your texture size to 256. When you first start AHII click on the video setup, change texture size from 512 to 256.
If these don't work:
3) Take two aspirin and call HiTech in the morning.
