The recordings sound like chipmunks when played back in iTunes.
Check your Audio/MIDI Setup. Open your Applications folder from the Finder, and scroll through the applications, down to "Utilities." Select that, and then choose "Audio/Midi." From here, set the "Properties For" or "Settings For" to iMic USB Audio System. Then set both the input and the output to 16bit 2 channel 44100Hz.