Yes, this is quite simple. Whenever you would trigger to go to the next layout, delay it a bit. Have a variable as something like "fadeoutmusic" and then set it to 1 when you would end the layout. This is also a good time to fade in an all-black tiled background over top of the layout to have it fade to black, but that's for another day.
-If fadeoutmusic = 1, set audio volume to Audio.Volume("yourmusictag")-200*dt
-Compare 2 variables
------if Audio.Volume("yourmusictag") < or = 0, Go to layout, trigger once