In fact, Audio on Safari-iOS has been intentionally crippled by Apple (its not "un-implemented" features, its intentionally-not-implemented features") so as to prevent any disruption of iTunes revenue stream from Audio-playing websites.
I imagine a simular API for sound would surfice.
Really? I guess 6% of it's net sales isn't a huge amount i guess, but when that equates to £6.3 billion I wouldn't regard that as small fish.