[General Topics] Elements1984:
Hello again :)

After around 2 hours of examining the mixer file as well as the build.prop, I made some modifications to the mixer but I am hoping these will fix your problem, you will be able to make further adjustments to the other settings once we are done with the bluetooth headset problem, so I will be looking forward to your feedback in order to know if it got better. I still have a couple of things to try which will not be necessary if this mod already fixes the problem.

The build.prop file had nothing that I could think of changing because it was very similar to the CM version you posted, but I could be wrong since I have very little knowledge when it comes to programming, my area of expertise is more into acoustics and such.

As for the sample rate of 8000 Hz that you got when you used the recording app, I can only say that I have seen in the xml that other rates are accepted, such as 41000 Hz (which is CD quality). I believe the standard in the past used to be 8000 Hz for phone calls but I am not aware of changes in the industry nowadays, but I don't see why it didn't give you access to higher sample rates which other apps such as Skype and Viber are possibly using. I suggest you try another microphone recording app to see if you have the possibility in the settings to choose different sample rates such as 32000, 41000 or 48000 Hz. Also, choose a format that can accept these rates (MP3 at 128 kbps will do), I am not sure the AMR format accepts these rates and I am pretty sure this is the recording format you used with your app for your last test.

As you noted, there may be much more things involved than just the mixer xml file, so you should proceed one step at a time, I suggest you wait a few more days before moving to the solution of moving everything from the CM audio files to the Stock one you are using, I am willing to help you as much as I can. I can already tell you that copying stuff from one rom to another will not work because some code lines will be looking for files that do not exist on the target rom, or they could be having a different name, that's why it's important to pinpoint what is needed for what before copying things.

I have found a couple of things that you could try also, since some people reported that this fixed their problem, this solution looks possible to me since the stock rom comes bloated with preinstalled apps such as google apps where as a CM rom comes clean and people usually only install a micro gapps, which in your case it could explain why you get this problem only on the stock rom. So here is something to try:

"Posted by MurphysMagnet: I had a similar problem with my G3. I would call people and they were unable to hear me on the other end. I could hear them fine. This happened with the hardest, speaker phone or bluetooth.

Solution: Turn off the "from any screen" option for "OK Google" detection.

Google Now > Settings > Voice > "OK Google" detection > from any screen

Turned off it will still work in Google Now and on the home screen with the widget.

Calls are all clear now and everyone says they can hear me fine."

Here is the Mixer XML that I tweaked using the CM xml as a reference, there are some microphone settings that I increased even further and a couple lines that I copied from the CM file which I don't know if they will be taken into consideration by the stock rom, I hope this will fix the problem.

Here are the lines that I added to the Stock XML:

Line 506 + 507 in CM xml to 556 + 557 in Stock

<ctl name="INTERNAL_BT_SCO_RX_Voice Mixer Voice2" value="1" />

<ctl name="Voice2_Tx Mixer INTERNAL_BT_SCO_TX_Voice2" value="1" />

Line 511 + 512 in CM xml to 563 in Stock

<ctl name="Internal BTSCO SampleRate" value="16000" />

<path name="voice-call bt-sco" />

I will be looking forward to your feedback, hopefully with some good news :D

Don't forget to hit the thank you button if you appreciate my efforts ;)