1. A method comprising, by a media-player device:detecting, by the media-player device, that a client system of a user is within a wireless communication range of the media-player device, wherein the media-player device comprises a plurality of antennas;
broadcasting, from the media-player device, an authentication key for the user of the client system;
registering, by the media-player device, the user to the media-player device based on the authentication key being verified by the client system; and
receiving, from the client system, instructions to adjust a power level of each of the plurality of antennas, the instructions being determined based on broadcast signals received at the client system and on a respective position of the client system associated with each received broadcast signal, wherein the respective position of the client system is determined with respect to a position of the media-player device.