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Description: Studies of cortico-motor excitability have shown that unexpected sounds are followed by motor inhibition. In a recent study, Leiva and colleagues (2015) derived a prediction from these findings: unexpected, task-irrelevant sounds should increase the likelihood of withholding motor responses in a Go/NoGo task. Contrary to that prediction, they found that playing unexpected sounds before NoGo-stimuli decreased the likelihood of successful motor inhibition. However, we here argue that the relative timing of unexpected events relative to NoGo-related motor activity is key. Cortico-motor inhibition can be found only until ~150ms after the onset of unexpected sounds. Since Leiva and colleagues placed their sounds 200ms prior to NoGo-stimuli, the inhibitory influence of unexpected sounds may have fully abated before the critical inhibitory period in their experiment. Consequently, we here repeated their study, with one key change: task-irrelevant sounds were presented 50ms after NoGo-stimulus onset, which ensures that cortico-motor inhibition takes place when motor inhibition is needed. Across four experiments, this changed timing produced the results predicted by the previous cortico-motor suppression findings: more responses were successfully withheld after unexpected sounds. These data provide new evidence for the fact that unexpected events can engage an inhibitory control process and benefit motor inhibition.