GRIM/EMI: Positional sound tweaks

f8f7100 affects both Grim and EMI. In the original games voices are always played at the same volume and balance regardless of the talking actor's distance and angle to the camera. This is fairly easy to observe in sets where the camera is far from the actor. For example outside the DOD in Grim, and on the Melee island streets in EMI.

The other commits are EMI-specific fixes.