I believe it literally is choppy. Chipmunk voice happens when you compress the waveform, I believe the way they avoid that is NOT by compressing it and then som

I believe it literally is choppy. Chipmunk voice happens when you compress the waveform, I believe the way they avoid that is NOT by compressing it and then somehow shifting the pitch, but instead by sampling less of the waveform. So I believe 2x is literally playing only half of the audio. I hope to be corrected if I am mistaken.