Many popular devices and software programs support M4P format specifications such as iPad, iPhone, Quick time player, and Windows media player 12. M4P allows you to enjoy videos and movies but it takes more space. This is one of the reasons you prefer to convert from M4P to MP3.
A number of Apple users would have the need to convert M4A to WAV, because some people would need to play the M4A file on other devices, so this would be WAV file. If you also want to convert M4A to WAV, then you can check out this article as it recommend the top tools to convert M4A to WAV.