However, you can play these iTunes M4P files on you HTC Touch Diamond by converting these M4P files to plain MP3 or AAC format, with NoteBurner for Mac (download here). NoteBurner M4P Converter is a DRM copy-protected audio and music converter designed for burning DRM protected music to a special virtual CD-RW drive where you can quickly get unprotected MP3 or AAC files ready for use on your HTC Touch Diamond. Unlike other audio recording software products, NoteBurner is a virtual CD burner emulator which easily emulates the whole workflow for converting music or audio files to normal music files: ripping, burning, encoding are within only few clicks.

NoteBurner audio file conversion software for Macintosh is a sound file format converter for Mac. It can convert audio files from many different file formats into mp3, or aac files such as M4P to MP3, M4P to AAC, M4B to MP3, M4A to MP3, M4B to AAC, M4A to AAC, WAV to MP3, mp3 to AAC, wma to mp3 and much more.