What file format does iTalk Pro use for recording?
The file format is specified by the connected iPod, and you have 2 options. You can record 16 bit WAV files at 44.1 kHz, or 16 bit WAV files at 22 kHz.
To change between these options from the main iPod menu, choose Extras > Voice Memos > Quality and choose either High or Low.
High quality recordings will sound better, but will be larger files than Low quality recordings. Try using Low quality if you are only recording speech or do not have much space available on your iPod.