I had a problem with synchronizing my Serenata from my mac. But I've managed to solve the problem! The Serenata didn't recognized the music i put in the music folder. But with Disk Utility (a program standard on every mac), now everything is okay.
How does it work:
First make sure your Serenata is connected with your mac, and set it to massastorage
Then simply open Disk Utility (schijfhulpprogramma (dutch)).
and click on the Serenata Disk where you normally put the music.
-Click on the tab Erase
Then again on Erase (at the right bottom) Make sure your disk name is still 'Serenata'. Now the computer starts erasing all the files on your Serenata disk memory. (if you have important files on it, make sure to copy them)
When it's done, eject the Serenata! And get it of the USB.
Then simply plugin your Serenata again, make sure it is in massa-storage mode.
And put the musicfiles on it.
Another tip! ITMW Itune My Walkman is a simple but clever programm to put music files on an usb device. I use it for my Serenata. Make sure you select the destination folder 'Music on the Sefenata. And set it to synchronize your favourite playlists.
I hope this is helpfull for Serenata owners with a mac!