Soundmap?

This is the essence of what I use:

;-----------------------------
Function PlayerDetCollText()
;-----------------------------
Local collcnt
Local SURFACE_Level,BRUSH_Level,TEX_Level
Local success = 0

	If (EntityCollided(hEntPlayer,TYPE_TERRAIN)) 
		DetCollTextName$ = "TERRAIN"
	Else
		collcnt = CountCollisions(hEntPlayer)
		If collcnt>0
			SURFACE_Level = CollisionSurface(hEntPlayer, collcnt) 
			If SURFACE_Level > 0
				BRUSH_Level = GetSurfaceBrush(SURFACE_Level) 
				TEX_Level = GetBrushTexture(BRUSH_Level) 
				DetCollTextName$ = Upper$(TextureName$(TEX_Level) )
				FreeBrush(BRUSH_Level) 
				FreeTexture(TEX_Level) 
				success = 1
			EndIf
		EndIf
	EndIf

Return success
End Function

DetCollTextName$ gives me the texture name of what I'm walking on.
Then I have a lookup list of texturenames > sound files.
The appropriate sound file is 'marked' for next use, and is then played after a timer-count has expired.