Audio Loading Issues

I am currently designing a site that has a looping background audio piece, however, within this movie there is a section that’ll have another piece of audio in it, (eg. restaurant sound in background).

I have a on/off button that controls all the audio, but what i want to happen is when the main audio piece to turned off the other audio piece is still allowed to play…

I’m sure someone has had this problem before…so any help would be greatly appreciated…

thanks

chef