- when in single player, always play talk sounds from the player actor.

It seems some places manage to play these sounds from undefined actors that may or may not be in range.
Fixes #75

source/games/duke/src/sounds.cpp

@@ -388,6 +388,14 @@ int S_PlaySound3D(int sndnum, int spriteNum, const vec3_t* pos, int channel, ECh
 			});
 		// don't play if any Duke talk sounds are already playing
 		if (foundone) return -1;
+
+		// When in single player, force all talk sounds to originate from the player actor, no matter what is being used to start them.
+		// Fixes a problem with quake06.voc in E3L4.
+		if (ud.multimode == 1)
+		{
+			spriteNum = pl->i;
+			auto sp = &sprite[spriteNum];
+		}
 	}
 
 	int32_t sndist;