This is completely out of my field, but would it be possible to dope a soundtrack with an audible signal to extend your bandwidth, without the actual music caus

This is completely out of my field, but would it be possible to dope a soundtrack with an audible signal to extend your bandwidth, without the actual music causing more interference than the extra bandwidth is worth? I'd assume that you should be able to predict the type of background noise created by the soundtrack reflecting off a person sitting in front of a computer at a predetermined distance. In 90% of cases we're going to be talking a person sitting in front of a desk. Again, this is way out of my ballpark.