Smooth high-speed playback

Thanks for any help.

Is there a way to make audio preview playback smoother when playing at 4x speed?

To clarify:

On a timeline I press play (L), then press it two more times for faster playback (LLL) which gives me video played back at 4x.

The audio plays back very cleanly at 2x. Is there a way to improve the understandability of the playback at a higher speed?

Scenario:

I am listening through presentations to scrub pauses and any "um's" and "uh's." If I can just barely understand what they are saying, that's enough to do what I need to do. This is possible if the sped up audio is clear. At present, it's just slightly choppy. Is there a way to make it any more smooth?

Ideas:

Maybe decreasing video quality itself would help process audio better? Or maybe conforming audio into a more manageable format? As-is, it's already good. But I'm trying to squeeze every last bit of understandability out of this. Over the course of the 80 hours of content, I stand to save maybe 20 or more hours of work if I can listen at 4x speed.

Thanks much!