Increased voice chat volume
Several people have complained that the volume of the voice chat is too quiet in comparison to the sound effects and music, even if the input/output volumes are set to the max. Admittedly, when I worked on the voice chat months ago, my SFX and music volumes were very low, so I had no trouble hearing myself or other players. However, once they're raised to the max, it becomes extremely difficult to hear anyone's voice.
I arbitrarily increased the amplitude of the user's voice during recording by 25-fold, so this should make it easier to hear the voice chat, especially when the sound effects and music are loud.