UPDATE: For those with Custom Rom experience, work around: https://www.youtube.com/watch?v=A9ttOOPBsAU&t=1s
(strawpoll - http://www.strawpoll.me/11905470/r)
New Video: https://www.youtube.com/watch?v=B2JLzRkX7HE
This video demonstrates the static/popping/crackling noise that is an issue across both the Google Pixel and Pixel XL. This is an issue that I have personally seen on 5 devices and I am not the only one (https://productforums.google.com/forum/#!topic/phone-by-google/XDl52F-Np6o)
This is an issue that Google needs to acknowledge and correct.