I can’t hear any sound when I preview a ringtone.
Firstly, check that your phone is not muted. It sounds silly, but it’s an easy mistake to make.
Check that your iPhone volume is turned up while an audio preview is playing inside the App. iPhone has 2 different volumes – one for the ringer, and one for other audio. The one for other audio can only be adjusted when audio is playing back, such as when you are listening to iPod, or previewing sounds in ToneRack.