Try OGG/Vorbis, the latest one, SAM Broadcaster Encoders via Pipeline, and Modified (latest KH) Icecast, with setting of "<burst-size>0</burst-size>" in the config file and you can get as good as <100ms. Tested via City connection (we have fast Fiber-optic Internet everywhere, local speed is at 100 mbps) <1ms ping between the 2 machines, 17km apart from each other, the lag is minimal, below 100ms.