Minor fixes to SetTopLevelSoundSet

Author: garethyr

Entities/SoundContainer.h

@@ -92,7 +92,7 @@ namespace RTE {
 		/// Copies the passed in SoundSet reference into the top level SoundSet of this SoundContainer, effectively making that the new top level SoundSet.
 		/// </summary>
 		/// <param name="newTopLevelSoundSet">A reference to the new top level SoundSet for this SoundContainer.</param>
-		void SetTopLevelSoundSet(SoundSet &newTopLevelSoundSet) { m_TopLevelSoundSet = newTopLevelSoundSet; }
+		void SetTopLevelSoundSet(const SoundSet &newTopLevelSoundSet) { m_TopLevelSoundSet = newTopLevelSoundSet; m_SoundPropertiesUpToDate = false; }
 
 		/// <summary>
 		/// Gets a vector of hashes of the sounds selected to be played next in this SoundContainer.