This paper examines what happens when a digital audio signal is measured with respect to a digital reference signal that was created based on a different clock. The resultant change in frequency and time depends on the degree of mismatch between clocks and may introduce a significant amount of distortion into the measurements. But the distortion is different from the types normally considered important in audio systems and may obscure other types of distortion, e.g., harmonic, IMD, and noise, that are more important to accurately assess. A difference in clocking essentially creates a difference in sample rates. Therefore, sample rate conversion methods can be used to mitigate the discrepancy. Although this approach is effective, it cannot be used when the sample rate difference is too small, it can be computationally intensive, and it cannot entirely eliminate the effects of a clocking difference. This paper describes a much simpler and more effective technique that requires minimal computation.
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https://aes2.org/publications/elibrary-page/?id=19781
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