Simultaneous playback with a minimum of two players is supported. Mixing
depends on available device resources; at least one player is supported with
possibly two or more if resources permit. Players can be of any content type.
Support for mixing can be queried from the property supports.mixing.
Processing power requirements for a player vary depending on the content type. Simultaneous playback of two players with the same content roughly doubles the needed processing power; therefore, it might not be viable to mix multiple players of the same format.