AudioScope
Can a Peak Hide Between Samples?
A sample-peak meter reads the stored points. A true-peak meter estimates the level between them. This diagram shows how a waveform can reach higher than any of its stored sample values.
Why the meter readings differ
The dots represent stored sample values. In this illustration, the reconstructed waveform reaches about 3 dB above the largest stored sample. The size of the gap depends on the signal.
A true-peak meter uses upsampling to estimate the maximum between samples. Leave headroom and check the final export with a true-peak meter.
ITU reference for true-peak measurement