Most telephony I've experienced has latency measured in seconds (if you ever call your friend or spouse sitting next to you it becomes very obvious :) vs audio recording and processing which is measured in milliseconds.

Additionally, from what little I'm aware of, telephony is heavily optimized for particular frequencies of human voice and then heavily compressed within that. As well, any single telephony stream is basically a single channel. A song may have dozen of channels, at high resolution, full spectrum, all sorts of computationally demanding effects and processing, and still need latency and sync measured on milliseconds.

So... Kind of the opposite of each other,while both being about processing sound :-).