Hi @nstvns -
I would find that annoying too.
Have you tried modifying playback speed from your queue? See screenshot. When I do this, it actually does function as a global setting…

If your queue currently has playback set at 1.3, then try bumping it up to 1.4 just to test it out…if that sticks, then toggle it back down to 1.3.
Last thought. My unsolicited 2¢, fwiw. Deleting/reinstalling the app was a reasonable recommendation from the support team => if you happen to have a buggy setting cached in doc/data on your device, that should clear it. If you have issues with the above approach, then I would suggest doing this and trying again.
Good 🍀!!