I have a Mobile In and am using it on an iPad 2. Its a great tool but I can't get thge out put to play thru my comp speakers. I have the cabl running from the 1/8" headphones out to my soundcard but cannot hear anything. I can play thru an amp just fine though.
You may need to configure your soundcard so that the input is active. You'd need to check with your computer's documentation for that.