Honest question: if these become ubiquitous (i.e. the majority of OEMs remove the headphone port on phones and everyone uses some kind of wireless headphones) w

Honest question: if these become ubiquitous (i.e. the majority of OEMs remove the headphone port on phones and everyone uses some kind of wireless headphones) wouldn't the interference make them unusable in a crowded place? How many channels are available, and is that enough for a whole bus full of people using wireless headphones?