Speaker on watch 6 muffled…solution may work for you.

Clean out the speakers with a very thin piece of metal (I used the tip of a nail nipper tool. Scraped the inside very gently to reveal has a “crunch” sound. Sand from our beach visit? Salt from the water or our pool? Sweat from running? Either way it helped! Apple wanted to charge $300 for a repair….it cost that much new!! Try this first. Use your old voicemails to gauge the sound quality. Good luck!!