gdgt

I have no Mac Experience, but I have installed free 3rd party firmware 'Rockbox' on mine, and it has made my Sansa even better in my opinion. 'Rockbox' has way more options and customizations and a much better interface. I believe it is supposed to work with Macs as well so you might want to try that out. It really is cool, plus it comes with a few simple games so you can entertain yourself on the tiny screen if you're on a bus or something. This might solve your problem. Rockbox.org

Oops I've just read this on the rockbox website under "Known Issues.......in the current release (1.2.2):"

(OS X) Complete / Small Install is not working correctly for Sansa / Apple players: bootloader installation unmounts the player (required), but the build gets installed before the system can remount the player. You need to use the separate installs from the "Installation" tab for now.

So you may have to troubleshoot the install for a Mac, the site usually is pretty good about explaining what to do if you just taking things one step at a time.

I second putting on the Rockbox firmware, but the stock Sansa firmware should also work with OS X. Just make sure the Sansa is in mass storage mode. If it's similar to my E200 series, it's buried in the settings menu somewhere. You need to change it from MTP to MSC. Then it should just show up in the Finder as a flash drive when you plug in the USB. Drag and drop files directly from iTunes. Alternatively, you may want to either check out SyncTunes (www.nesfield.co.uk­/synctunes/) or search Doug's Applescripts for a way to more easily transfer playlists. Using an AppleScript will require some minor edits to reflect where you keep the music files and the name of your Sansa, but should work for "one playlist at a time" transfers.