I’m not sure if this is a new problem to iOS6, but there are various reports on the web about audio being initially muted in iOS in the Web Audio API, see http://stackoverflow.com/questions/12517000/no-sound-on-ios-6-web-audio-api, but I’m not sure if something has changed in iOS6 or whether this has always been the same.
The MoonWarriors example doesnt play any music on an iPad running iOS6. The only sound that is played is the buttonEffet.mp3, - and I suspect this is played because its response to user input.
BTW. on Mac (Lion), MoonWarriors works fine both in Safari and Firefox.
So this looks like a “mobile” safari issue.
BTW. I’ve also noticed that despite putting my sound resources into the resources.js to preload, the sounds do not appear to be being preloaded. So that the first time they are played they take a long time before any sound, but subsequent calls to playEffect make the sound play much more quickly.
You may also want to read this article I just found http://buildingwebapps.blogspot.com.au/2012/04/state-of-html5-audio-in-mobile-safari.htmland this http://www.ibm.com/developerworks/library/wa-ioshtml5/index.html