SimpleAudio's HD sound system (simpleaudio.co.uk) might be a good option. It runs on an IP network and/or powerline AV tech and it supports 24/96, though its dealer-only and looks a bit pricey. Apps for iPhone and Mac/Windows.
There is also audio|acacia multi-room music (www.plethra.com) currently in beta. Its wired or wireless and can work in a central wiring config. Not sure if it supports 24/96 but it does have digital out so you can use your own DAC and has apps for wifi devices (desktop, mobile, tablet).