While the 3.5mm AUX audio cable for TV is inserted into the Aria Line M, you can use the remote to switch between Mono and Stereo modes. Locate the switch on the remote and slide it to select your desired sound mode.
Mono mode: only one channel is used for the sound. You will hear the same exact sound from both sides of the headphones.
Stereo mode: multiple channels are used for the sound. You will hear different sounds coming from either side of the headphones.