Sarisio: What Operation System do you use? I always had problems with launching MM 8, GOG version comes pre-patched with compatibility patches. On Win-7, however, I had to right-click on MM8.exe and set compatibility with Windows 98. make sure you don't have hardware sound enabled in config.

In case you use Windows XP, you need to launch dxdiag and disable hardware sound acceleration (even though MM 8 says about DirectDraw error, it might not be the real case).

If all this fails, google old distributives of DirectX 6 and/or 7 and install them. It won't make your DirectX suddenly become DirectX6, it will only copy missing files.