My Sansa Clip Zip battery is dying. It will not hold a charge for very long (4-5 hours) where it used to last 12+. I was looking to replace it and get more capacity, but just about every MP3 player I look up that has expanded capacity, when you dig deeper you find out that their firmware will only handle 4000 songs. I want one with a 32 GB card. I can put over 8000 songs on that at 128 kbps, but if the firmware only allows 4000s, what is the use? My Clip Zip only allows about 4000 and if I put more than that, many folders will not show in the menus. Very frustrating. Can't figure why these companies can't put the limit higher in the firmware.

I am looking for suggestions but have a few criteria:

Long battery life (min 15 hr, prefer much longer)
folder selection and organization of music
drag and drop loading music
USB mode to connect to Linux OS
keeps its place when shut off
holds and displays as many songs as can fit the drive and card
clip to hold it to my undershirt
Prefer a charger that cannot over charge (APGTEK says not to charge more than 3 hours)
not too pricy (I might go close to $100 for a really nice one)

Alternately, I keep using my Clip Zip and carry an auxiliary battery that you can plug into if needed.