Maybe - in my experience with this, when the devices are within a foot or so, there really isn't much packet loss, maybe as low as 10^-6 or so. But I haven't re

Maybe - in my experience with this, when the devices are within a foot or so, there really isn't much packet loss, maybe as low as 10^-6 or so. But I haven't really explored moving further apart. I suspect that this suffers from a sharp knee where it starts out reliable and then very quickly fades off. To be clear, the 7kbps is the raw frame throughput, not the effective rate with TCP. There are two ways I can see to boost this number. One would be to pack more bits into each symbol, e.g. to use a wider QAM mode. I find that in practice the degradation from using speaker/mic makes this somewhat impractical. The other would be to use a more broadband signal (the width of the the main audible channel is a few kHz). But this is also kind of undesirable since it has to compete with more interference across the spectrum and can also be a less pleasing sound.