... USB, pcb -memory function:FM,volume -Max vol:26 -last/next songs,vol,Pla/Pau,repeat,mode Decoder Board with FM radio for ... SD card,usbFunction and features: SD/MMC/USB Card MP3 Decoder Board, ... , it has such switching order as USB→SD→FM→USB; When only with USB flash drive, it has the switching ... you press this button. Decoder Board with FM radio for SD card,usb