http://www.techradar.com/news/google-pixel-2-xl-audio-recording-problems-reported-fix-on-the-way

Google's Pixel 2 XL problems aren't going away as another issue with the new smartphone has cropped up, though Google promises a fix soon.

Some users on the Pixel User Community forums have reported "very bad" sound quality when recording audio. Users describe the sound as high pitched and tinny.