The brain gives "precedence" to first arriving signals that are presumably louder in an acoustic situation. In an electroacoustic situation, as described, raising the level of the sound in a given speaker will likely override the first arriving signal which will now be weaker.
In mixed acoustic/electroacoustic situations, such as a PA system, the signal arriving from a speaker that is closer to you than the acoustic source, will also determine its apparent location (but unless you close your eyes, you may not realize that the sound is not coming from the visual source).