Video playback problem in Safari Mac

YouTube slows down in Safari on Mac 2019 (Sonoma). The video plays normally for the first 30 minutes, then the following type of lag begins: the video "frozes" for a few seconds (the sound continues to go), and then the video, as it were, "catches up" with the sound in accelerated playback. In the Google community, the issue is marked as a copy, no one says anything how to solve it. In other Chromium-based browsers, everything is fine. How to solve it, caches, cookie files were cleaned - there is no result...

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