Display device for outputting audio

A display device comprising:

• a wireless communication interface connected to a plurality of sink devices that output audio of content;
• a display configured to display a content list including a plurality of content items respectively corresponding to a plurality of content and a plurality of sink device lists respectively corresponding to the plurality of content items;
• and
• a controller configured to:
• obtain a plurality of sound sources respectively corresponding to the plurality of content, and
• generate a plurality of sink sound sources respectively corresponding to a first content item and a second content item based on different sound sources among the plurality of sound sources,
• wherein the controller is configured to concurrently transmit:
• (i) a first sink sound source of the plurality of sink sound sources to a first sink device of the plurality of sink devices, and
• (ii) a second sink sound source of the plurality of sink sound sources to a second sink device of the plurality of sink devices, such that audio corresponding to the first sink sound source and audio corresponding to a second sink sound source are output concurrently via the first sink device and the second sink device, respectively,
• wherein the controller is further configured to obtain a user input for selecting an audio output method, when receiving a user input for selecting an identical sink device item from two or more sink device lists among the plurality of sink device lists, and
• wherein the audio output method includes a simultaneous playback and a sequential playback in the selected identical sink device item.