Post 2.0: After exiting a vendor's menu in the Tower, sound effects are not present for a short period of time. (dismantling items, footsteps, adding legendary and/or exotics to your inventory, etc.) This has not happened every time. Pre and Post 2.0: Occasionally, while in a firefight, all audio drops out. It usually lasts about fifteen seconds. Dialogue is usually the first audio to come back. The other world sounds slowly fade back in. This may be coincedence but it seems to happen slightly more often when fighting the Hive. It happens for me probably once every four or five hours of play time.