Magfan - Airfoil is to send sound from any application (or system) to AE. Without it AE only works with Itunes. AE worked with "Front Row" with previous OS but Apple disabled it in Leopard. A lot of people wrote to them about it but they are unresponsive and Snow Leopard has the same problem.
During gap between songs Airport Express stops sending data and DAC goes to "mute" (since there is no valid signal). My Benchmark DAC1 is fast enough to come back but some other DACs extend mute to second of two of the next song. Your DAC might provide substitute clock. Play with "crossfade songs" in Itunes to remove gap.
During gap between songs Airport Express stops sending data and DAC goes to "mute" (since there is no valid signal). My Benchmark DAC1 is fast enough to come back but some other DACs extend mute to second of two of the next song. Your DAC might provide substitute clock. Play with "crossfade songs" in Itunes to remove gap.