How do I troubleshoot inconsistent call quality? I have a OnePlus One phone that has worked great for a long time, but for the past few months, my call quality has been inconsistent. I am on the newest stock rom - Cyanogen12.1.1-YOG7DAS2K1, build LMY48Y - Android 5.1.1. Even though my signal bar shows strong signal, the person on the other end says I keep cutting out and they can't hear what I'm saying. I can always hear the other person fine. This continues for the duration of the call. If I call back, they can then hear me okay. If not, I'll call back a 3rd time. Once connected, my voice either cuts out the whole call or it doesn't. (This doesn't change during the call).

How would I go about troubleshooting this? I'm on Straight Talk with AT&amp;T coverage, and my signal strength is always showing very high. I get 20+ Mb/s download speeds with LTE. I'm not sure if this is a hardware, software, or cell service issue. Is it worth doing a factory reset on my phone or changing the ROM, such as going to their newer OxygenOS?
I experienced a similar problem on my OnePlus One a few months ago. I fixed it by disabling "Ok Google" detection from any screen in the Google app settings.

Apparently, the always on voice detection interferes with the voice in the call and hence the other person is unable to hear. It appears to be a Cyanogen bug.