Safari Browser - Poor Audio When Video Speed Increased Beyond 1.0x

Issue:

When watching a YouTube video at normal 1.0x speed, the audio is fine. If you attempt to speed up the video to 1.25x, 1.5x, 2.0x, the audio becomes increasingly more tinny, gravelly and distorted. This audio distortion occurs on pretty much any site that offers video content with the ability to increase the speed beyond 1.0x in the controls.

Troubleshooting Steps:

Chrome and Firefox do not have this audio distortion issue when speeding up videos, and the audio is still crystal clear on the exact same sites using the same computer. This Safari audio behavior is reproducable across all 4 of my MacBooks at home, while other web browsers render the audio just fine. All computers tested are recent model MacBooks running High Sierra, and are up to date.

Analysis:

This audio distortion issue seems to be a rendering problem with the way Safari handles audio playback when playback is faster the 1.0x. It might be an oversight in a design aspect within the browser, or a possible bug. I am sure many people are experiencing this behavior (or can easily reproduce the issue) with Safari when on YouTube and other sites that offer video speed controls. Try it out, and see if you experience the same audio issues in Safari vs. Chrome.

After running the tests across 4 MacBooks, I am convinced this issue is not due to browser cache, Safari settings or any configurable part of Safari, but rather something that Apple needs to assess and repair in a later release of the browser.

I hope that Apple see this post and is able to isolate the issue. If you have any further comments, findings or suggestions regarding this issue, please leave a reply!