Press any key on the touch-sensitive TS22 panel to hear sound bars playing the video soundtrack. Press the Bluetooth button and the 1725M-BTS becomes discoverable to pair with a phone or other Bluetooth media player. Once paired, Bluetooth audio plays through the selected sound bar until the timeout, or until you unpair your device. To switch to TV sound the touch panel sends a command to the media player to switch its audio output from optical to HDMI.