Does the device itself show folders and then tracks under the Playlist folder? If so you may have too many folder levels for the car stereo.

PS. Make sure the Playlist has tracks on it as only tracks added the last 7 days would be on it and thus if no tracks were added it would be empty.

Lowlander,

Thanks for the reply my friend! I guess I should have been more detailed in my original post but the issue is when I connect my Android (HTC Thunderbolt) to the stereo in my car via USB I can only use the stereo to browse and it only recognizes folders containing mp3's (not playlists for some reason). Thus, I'm trying to somehow get MM to sync songs added to the library in the last 7 days (for example) into a specific folder (like "Recently Added") on my Android.

This is the heirarchy I have now under "Sync Music files to" (which my stereo likes):
\Music\<Artist>\<Title>-<Artist>

I tried what you suggested (creating an Auto-Playlist of songs added in last 7 days) and using this hierarchy:
\Music\<Playlist>\<Artist>\<Title>-<Artist>

My stereo would show the <Playlist> folder names, but says they don't contain any music files...

Any insight?

<Playlist> mask is available for use so an Auto-Playlist with added last 7 days tracks could do the job (but it may cause issues with other files). Of course if you do sync a Playlist with last 7 days tracks you could use it instead of folder navigation to find the files.

I have been able to sync songs to my Android by "Date Added" by creating a playlist with those parameters. But my question is...

Is it possible to have songs added in the last 7 days (for example) to a specific folder on my Android?

THANK YOU!!!