Suggestion: Voice Chat Groups, or "Corners"

My friends and I like to hang out all in one voice channel so we can all joke around, but often some of us will be in one game and some in another, where communication is important to the game. Currently what we do is slightly lower the voice volume of people not in the game with us, but that requires us to readjust it constantly. We'd appreciate if there were some option to group people into groups within the same voice chat, as if they were standing in the same room but grouped into different corners. Either automatically by detecting what game we're playing, or manually by establishing sub-channels within a voice channel. Perhaps volume for people outside the group could be lower persistently, or perhaps only when a group member is talking, or perhaps non-group-members are silenced entirely when a group member speaks. Perhaps we could make ourselves heard to people in other groups by actually raising our voice, or perhaps there could be a key for it.