The airplay system is quite good but very apple centric, I have a 3rd party app Airfoil, installed on my pc, this basically captures all audio and sends it out over wifi to any connected airplay devices, i have an apple tv plugged into my A/V amp, so audio can be picked up on this, as well as an app called AirView on my
iPhone that allows it to become an airplay receiver(rather than the usual set up where the phone only acts a airplay sender.)
My understanding is that Airplay is essentially a bastardised version of the DNLA standard, so hopefully there is a solution that would work with other hardware that mimics this functionality.