The background of 900P and 900T uses the built-in data on the hard disk as the MIDI background. In order to reduce the workload and increase the life span of the optical disc drive, it will not work when playing MIDI songs. It is mainly used for DVD or VCD or self-recorded background. The self-recording background function requires 900P 3.0 program or above to have this function. If you want to directly play the DVD as the background, you must use external means.
