... on-off , echo, key control, tempo, Melody volume control, favorite songs reserve, random play, repeat, continuous play; Compatible: DAT, AVI, ... SD card can contain more than 20,000 midi songs 4.Support Songs' Language: Chinese, English, Vietnamese, Tagalog, Spanish, ... songs with vocal and live background; 6.Full customize background function. Interchangeable background for user to add their favorite ...