Problem

Recorded audio signals, especially from instruments, sound glitchy and incomplete, with the sound cutting out. For example, guitar notes cut off unexpectedly, or only the transient or percussive parts of the sound get recorded. In some cases, the monitoring might still sound fine, even though the recorded signal is noticeably different.

Background

macOS offers "Mic Modes" that can help suppress background noise. This can, for instance, improve audio quality during voice calls in noisy environments. But if one of these Mic Modes is applied to a signal that isn't a spoken voice - like an instrument, for example - signal components that are actually desired are incorrectly identified as noise and are accordingly reduced, filtered, or suppressed entirely.

Solution

1. Make sure Cubase is running.
2. Click the orange microphone icon in the menu bar.
3. Select Standard as the Mic Mode, not Voice Isolation or any other mode.