The Sansa plays .mp3, .wma. ogg, FLAC and .wav.It can’t decode m4a or mpeg-4.
Are those iTunes downloads? Apple doesn’t want you to play them anywhere but on your computer and whatever that dopI little pocket music player they make is called? M4a and .aac are Apple’s proprietary formats.
Either you have to rip those files again from CDs into mp3, or if you don’t have CDs you need to convert m4a to mp3. Get the free Media Coder and convert (transcode) those mp4 files to mp3 at high quality, 192 kbps or above. If you use lower quality mp3 you will save space but the sound quality will suffer.
And if you were using iTunes to rip CDs, you can change the settings (in Edit/Preferences/Advanced/Import Music, which is different from the visible Advanced tab) to make mp3 instead of m4a files when you rip.
If your files are m4p, the p is for protected and those are copy-protected files, which means you are not supposed to move them onto another device. The only way to convert them is to go into the hacker underworld.
Message Edited by Black-Rectangle on 04-13-2009 10:28 PM