[laserbeam]

Irrespective of the patent details, this is actually a fun and not at all straightforward hardware project to implement. I had a failed attempt at this in uni, and synchronizing audio across multiple computers (rasps) is a really cool challenge.

[izacus]

But did you pay the rent to Sonos while you were doing that project? It's, after all, their intelectual property now.

[texasbigdata]

You don't know the year he/she went to University.

[boondaburrah]

you do know that raspis were involved, so it can't be before 2012. However, AirFoil/AirPlay existed before that and could do this.