Playlist sync problem

The FAQ was pretty unhelpful!

For a start it is not accurate because the playlist does not need to be in the same directory as the files. I have playlists that work when in different branch from the root directory. 

I use M3U playlist files and I have used MediaMonkey, WMP, Winamp and Songbird all without success.

Maybe a more helpful piece of information would be if there is a maximum amount of files that can be in a directory, how deep the file structure can be or how many characters the file path can be.

I already know how to make a playlist as my original post stated because I have used a Clip+ for a year without any issues and an iRiver for 6 years before that.

Please don’t think I do not appreciate you trying to help me I just think pointing me to an FAQ which isn’t an FAQ does not help.