In everyday language we say that something is audible when it is spoken loud enough to be heard.
“Audible” has another meaning in football terminology. The quarterback may have the option of calling an audible when the offense lines up to run the play that has been called in the huddle but, because of the way the defense is lined up, the quarterback sees that another play might work better and so he calls out that play at the line of scrimmage.
O God, make your still small voice audible enough to us that we can hear it deep in our spirit. Then, having heard your voice and having observed and analyzed the situation that presents itself to us, help us to make whatever adjustments and changes we need to make to deal with what is going on.
Help us to listen to you and to our situation and then to respond appropriately.