When I first got the 6P, I had terrible call quality when using it without a BT headset. After I got the S7 Edge, only then I realized why. When I use my cell phone without a BT headset, I sometimes lean it between my left shoulder and my ear, the way one does...
It turns out that the mic used to cancel out background noise is blocked when I do that with the 6P because it's location is just below the camera. On the S7 Edge on the other hand, this noise cancelling mic is on top of the phone, so the same thing doesn't happen.
So to solve this, I either use a BT headset, or hold the phone upright to my ear so I'm not blocking the noise cancellation mic. That's sorted out all call quality issues for me with the 6P.
Posted via the Android Central App