A host device is connected via universal serial bus (USB) connections to one or more external devices with respective speakers. The host device synchronizes playback of audio through the speakers of the USB-connected external devices by requiring devices to implement a deterministic latency between receipt of a start playback request, and requiring devices to slave their audio clocks to USB start-of-frame tokens, and determining a buffered start time for starting data transmission to the respective USB devices. The buffered time equates to the current time of the USB host plus an additional time buffer. The host device waits until the buffered start time, and then starts transmitting the audio stream to the external devices, which, in turn, begin playing the audio data on the next available clock cycle, frame, or microframe.