iPhone 12 Pro Max sound issues.

My iPhone 12 Pro Max sounds horrible. All audio has a grainy sound to it. Ringers, music, podcasts, it all sounds grainy and horrible. I can’t find a solution to the issue.

Also, when I make calls there is no ring on the other end. I hear nothing at all, only silence until someone picks up. Or just total silence if nobody does. I keep having to look to see if it’s actually calling.

Are there any solutions? I’m deeply regretting buying this phone.