Bluetooth audio receiver USB computer sound card, 4 kinds of interfaces to choose a connection method according to your needs, 1, RCA, 2AUX, 3 optical fiber, 4 coaxial. Accept the mode. After the product is powered on, press and hold SEL to switch to the BT indicator. It flashes to indicate that it is in the pairing state. Turn on the mobile phone to search for YET-R30 and click pairing. The pairing success indicator is on. In sound card mode, press and hold SEL after power on, switch to the Sound card indicator, and select the applicable interface. Simple and efficient, suitable for Win7, 8, xp32, 64bit Linux MACOS