This seems to happen fairly quickly once a GPS activity is started. The UI acts as if music is still playing and it still responds to playback controls from the earbuds (play/pause, skip forward/back), but no sound is heard.
For me, the only way to recover is to go to the Headphones menu, disconnect, then reconnect. (It doesn't always work.) It's bad enough that I don't bother trying to use these earbuds on a run.
This doesn't seem to happen if GPS is not active. (e.g. Listening to music without starting an activity.)
Beats Fit Pro (similar to AirPods Pro first gen) and Jabra Active 65t work fine for me, except that I have dropouts/static while GPS is activated but before I start running. (I'm guessing it has something the combo of GPS interference and lack of arm motion when I'm not running.) IIRC, I would also have problems with dropouts with the Jabra earbuds during running, but it's less of a problem with the Beats Fit Pro.
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