We've recently had a large batch of Pixels and Pixel XL all with this issue. It can be resolved by reflowing the Audio Codec chip. We've done this on a few and its worked every time, we've also stress tested this fix over a couple weeks and the audio chip has not failed.
+
+
=== Update (08/27/2018) ===
+
[image|1530589]
+
+
This is the chip you can try reflowing. Be sure to protect the rest of the board when reflowing, too much heat will kill the board or disturb the baseband. Sometimes a reflow will not work in which case you have to replace the chip or try re-balling it.
We've recently had a large batch of Pixels and Pixel XL all with this issue. It can be resolved by reflowing the Audio Codec chip. We've done this on a few and its worked every time, we've also stress tested this fix over a couple weeks and the audio chip has not failed.