I've been using the ipod touch i-doser app using Skull candy earphones.
Specifically this model: http://www.skullcandy.com/shop/hesh-shattered-gray.html
So far none of the free Doses have worked for me at all, even Hand of God, i starting to think the app doesn't work at all.
I-Doser Premium App - Ipod Touch
Re: I-Doser Premium App - Ipod Touch
It takes some time, definitely. Ive used the blue version of those headphones and they work with the app. Are you following the guide built into the app correctly? That should help a ton.