An example playback device includes a signal detector, a signal emitter, and a communication interface. Audio content corresponding to video content being displayed on a display device is received via the communication interface device. The audio content is played. While playing the audio content, a first signal is received via the signal detector from a control device configured to control the display device. A second signal is generated based on the first signal and the second signal is emitted via the signal emitter. The display device receives at a signal receiver of the display device the first signal from the control device and the second signal at substantially the same time.