[Verizon Galaxy Note 4 Android Development] zediiiii:
Formal N910V on CPF3 Microphone issue Bug Report

Thanks for the kind response. Here is a verbose explanation of the microphone issue.

I'm running CPF3 on the cm-13.0-20160919-UNOFFICIAL-trltevzw.zip build using a N190V consumer edition. The issue was also present on cm-13.0-20160724-UNOFFICIAL-trltevzw.zip. This issue was also present and manifested the same way on Jasmine Rom 7.0 with the same phone, but not present in PaulPizzRom.VRU2CPF3.r-2. I never flashed stock unrooted Marshmallow, so I don't know if the issue recurs on that ROM. All ROM installs were entirely clean, wiping everything TWRP will wipe using standard procedures both before and after the install (I tried without wiping too), and did not use any Titanium backup restores (to rule that out as a variable).

I did not install any Xposed modules when testing for this issue, though the issue recurred with or without Xposed modules.

The issue manifests most obviously when "OK Google" does not work at all with correct settings. Immediately after phone calls, Google Now doesn't hear the OK Google hot-word for 10-20 seconds, though it will sometimes (not always) work if the screen is turned off then turned on. Sometimes, though not necessarily after a phone call, microphone input will stop working at all for any apps except the phone app. The only fix I've found is a hard reset (a soft reset doesn't work, nor does force closing every app open, uninstalling and reinstalling apps, etc).

Another app (PitchLab Pro) shows a nice error message when the program is opened while the microphone can not be accessed at the hardware level, so I use this to find out if my microphone is not working at all. Strangely, I can still make calls, though external headsets won't play sound or receive input. during the issue. Another user reported the same issue here, and a second user seems to be reporting the same issue here.

Installing S-Voice causes crashes and does not fix the issue. I've tried every combination I can think of to reproduce the issue: plugging in a headset, turning on and off speakerphone, running a music app, listening to google maps guidance, turning the screen on and off, allowing the device to doze, and using the video recorder, all at the same time and in different combinations. I still haven't figured out how to reproduce the issue. That said, it almost always occurs within a day or two of the phone being on. I recently flashed a nandroid backup of CM13 over top of the working PaulPizz Rom, and I haven't been able to reproduce the issue yet. I have not been able to reproduce the issue at all while booted into safe mode.

I think the issue has only occurred when I have been using a non-microphone set of headphones in the jack, and my suspicion is that the audio handler isn't changing states correctly.

Logcat shows several errors on a consistent basis (I've not caught a logcat when the issue is happening yet):

"15861 AudioRecord-JNI Error -4 during AudioREcord native read"

"31882 OMXMaster Error A component of name 'OMX.qcom.audio.decoder.aac' already exists, ignoring this one."

And this one in particular looks suspicious to me

"478 APM::AudioPolicyManager Error StartInput(1536) failed: other input 1534 already started"

I've linked a very short clip of a logcat showing the audio related lines surrounding the error above here.