This was the exact case for the 6P too. Apparently it was by design and iirc never fixed. I couldn't actually tell the difference on mine though.Wow I read people saying the bottom was louder but that is mental, when he covers the top it makes **** all difference. As above, my 2XL isn't that bad by a long way.
I'm gutted, Google have really dropped the ball with the Pixel 3/XL.