Problem with Alarm Clock Pro on Dock

I just bought alarm clock pro in the itunes store and when the phone is not connected on the iphone dock it works great, but as soon as I sit the phone on the dock it wont make any sound when the alarm goes off you just get the red bar saying touch to cancel the alarm.......... The reason I got it was to be able to see it at night and to also wake me up in the morning, it seems crazy that it wont make a noise when it is on the dock???