if you want to get mp3s onto you new samsung comeback, you have there way to complete this:

option 1 through New Samsung PC Studio
option 2 through Mass Storage
option 3 through Bluetooth

Option 1 New Samsung PC Studio
Important: For this method, the handset’s USB Mode must first be set to Modem.
click here for how to config settings USB mode for samsung comeback

To transfer MP3 files, from a PC, to the SGH-T559 (Comeback) handset memory follow the steps below:
WARNING: DO NOT DISCONNECT USB CABLE DURING THE MP3 FILE TRANSFER

Note: Files transfered with PC Studio 3 are copied directly to the handset’s internal memory storage (Music Folder) and not to the memory card if it’s present during the transfer.

Mass Storage

Important: For this method, the handset’s USB Mode must first be set to Mass Storage or Ask on Connection.
Click here for instructions.

Note: The instructions below assume a microSD memory card has previously been inserted as well as formatted by the handset to create the necessary folders
Plug one end of the data cable into the handset’s power/data port located
on the left side and the other end into a USB port on the PC
On the PC, open My Computer and double-click on the new Removable Disk (Hint:
it will be assigned a drive letter and, depending on system configuration,
may not be the only Removable Disk present)
Using Windows Explorer, copy and paste (or drag and drop) MP3 files
from the PC into the Music folder located under the new Removable Disk
After the file transfer is complete it is safe to disconnect the
data cable from both devices

WARNING: DO NOT DISCONNECT USB CABLE DURING THE
MP3 FILE TRANSFER

To transfer MP3 files, from a PC, to the SGH-T559 (Comeback) handset’s memory
card follow the steps below:
WARNING: DO NOT DISCONNECT USB CABLE DURING THE
MP3 FILE TRANSFER

Bluetooth

Note: Both devices must support Bluetooth FTP (FileTransfer Profile)

To transfer MP3 files, from another Bluetooth device to the SGH-T559 (Comeback) handset, via Bluetooth follow the steps below: