Stereo Reproduction in the Presence of Sample Rate Offsets

One of the main challenges in synchronizing wirelessly connected loudspeakers for spatial audio reproduction is clock skew. Clock skew arises from sample rate offsets (SROs) between the loudspeakers, caused by the use of independent device clocks. While network-based protocols like Precision Time Protocol (PTP) and Network Time Protocol (NTP) are explored, the impact of SROs on spatial audio reproduction and its perceptual consequences remains underexplored. We propose an audio-domain SRO compensation method using spatial filtering to isolate loudspeaker contributions. These filtered signals, along with the original playback signal, are used to estimate the SROs, and their influence is compensated for before spatial audio reproduction. We evaluate the effect of the compensation method in a subjective listening test. The results of these tests, as well as objective metrics, demonstrate that the proposed method mitigates the perceptual degradation introduced by SROs by preserving the binaural cues.