An example electronic device according to various embodiments of this document may include: at least one auxiliary processor; and a main processor operably connected to the at least one auxiliary processor, wherein the main processor may be configured to: obtain moving image data; separate the moving image data into image data including plural consecutive image frames, first audio data including plural consecutive audio frames, and plural timestamps corresponding respectively to the plural consecutive audio frames; generate second audio data using the first audio data by adding header data to each of the plural audio frames; transmit the second audio data to the at least one auxiliary processor; generate, based on first time information successively received from the at least one auxiliary processor, second time information; and play back the image data based on the second time information, and wherein the at least one auxiliary processor may be configured to: play back an audio signal based on the received second audio data; and generate the first time information about a playback time of the audio signal based on the header data.