In the upcoming content patch 2.2, the in-game sound engine is being changed to a new, exclusively software-based system. This change is being made to allow for a much greater range of compatibility and should result in improved sound performance for many users. The new sound engine provides all of the same features that have always been available in the game, but now extends those features, such as reverb effects, to players who previously couldn’t take advantage of them. This change also allows us greater control and ease in supporting and developing for the wide range of sound hardware, as well as future upgrades and improvements to the in-game sound effects and options.
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