The location of the song contents in JB-199 unit will differ between the old and the new. For the old units with a single partition hard drive, the songs are stored in a folder C:\NJB99\Songs. For the new units with dual partitioned hard drives, they will be in D:\Songs.
Right click on the Songs folder and select Copy. Do not go inside the Songs folder. Simply copy the entire folder. Next go to the external hard drive or any storage media you prepared and paste. Inside the Songs folder, there are many subfolders named such as JB000000, JB001000, etc. No need to concern yourself with the details as you should copy the entire folder Songs without going inside.
Moving to a new JB-199 unit, simply copy and paste the Songs folder from the external hard drive into D:\ drive of the new JB-199 unit. There will be already a folder call Songs in the D:\ drive. Rename the already existing folder Songs to Songs2, and paste the folder Songs from the external hard drive.
To test and play a song, be sure to go to MENU > 5. System Control > 9. NCG File Protection and set it to Off. Select a song and play to confirm the video and audio outputs.