I created a small example that reproduces 6 sounds at the touch of the mouse over an image for testing.

The sounds are in wav, mp3 and ogg.

snd_marca1: new ig.Sound( 'media/sounds/marca1.*'),
snd_marca2: new ig.Sound( 'media/sounds/marca2.*'),
snd_marca3: new ig.Sound( 'media/sounds/marca3.*'),
snd_marca4: new ig.Sound( 'media/sounds/marca4.*'),
snd_marca5: new ig.Sound( 'media/sounds/marca5.*'),
snd_marca6: new ig.Sound( 'media/sounds/marca6.*'),

In this way I first load OGG and working properly on Windows with Chrome.

If I change the order [ig.Sound.FORMAT.MP3,ig.Sound.FORMAT.OGG ] to try to resolve the problem the iPad does a one-time sound reproduction, each of them, then fall silent forever. When testing on windows.

Of course, there is no way to load the test on an iPad, or Safari, or Chrome. This issue of who's fault? of ImpactJS or IOS?

A little light on the subject? ImpactJS and HTML5 solution seems good. I tried some example of sound reproduction in the iPad that have nothing to do with ImpactJS but HTML5 and works without problem.

http://hpr.dogphilosophy.net/test/
http://www.terrillthompson.com/tests/html5-audio.html