Abstract: Systems and techniques are provided for audio synchronization and delay estimation. Audio metadata including a first discrete Fourier transform representation may be received. An audio signal may be pre-processed. A second discrete Fourier transform representation may be generated from the pre-processed audio signal. A correlation result in a discrete Fourier transform representation may be generated based on an element-wise multiplication of the first and second discrete Fourier transform representations. An inverse Fourier transform may be performed on the correlation result in a discrete Fourier transform representation to generate a correlated signal including samples that may have a position and a value. A relative delay value may be determined based on the position of a sample having a value with the greatest magnitude. Playback of a second audio signal may be adjusted based on a current delay value adjusted based on the relative delay value.