DGX-670 Recording Issue

I’m recording from my Yamaha DGX-670 piano directly to my laptop via the “USB TO HOST” feature. I don’t hear any issues with the audio while recording. However, when I play back the recording, parts of the audio sound muffled and their waveforms appear jagged.

I attached screenshots. In Picture 1, the areas highlighted in red represent the “bad” audio. Picture 2 represents a section of “bad” audio zoomed in and Picture 3 represents a section of “good” audio zoomed in. The waveform in Picture 2 appears to be spread further apart and has higher peaks and valleys compared to Picture 3.

Does anyone have any idea what could be causing this issue and how to resolve it? Thanks in advance.