I have a S22.
I opened my phones internal storage from the computer by connecting the usb cable to my laptop.
The below is the path for notification audio files.
\Internal storage\Android\media\com.google.android.gm\Notifications
I created a folder in the path I just shared and gave it the name Gmail-sound. The path is like the below now.
\Internal storage\Android\media\com.google.android.gm\Notifications\Gmail-sound
I created an audio by "Voice Recorder" which is on my phone by default.
The below is the path where my recorded audio files are.
\Internal storage\Recordings\Voice Recorder
I copied the Gmail-sound.m4A file and pasted into the below folder. (which I stated already above)
\Internal storage\Android\media\com.google.android.gm\Notifications\Gmail-sound
At the moment I've just added a new audio to the notification sounds.
Opened my Gmail app from my phone, gone into settings, then searched and found "notification sound" setting. And from there I choose Gmail-sound.M4a as my new notification audio.
I presume the same can be accomplished when you can download M4A audio files from somewhere and create a file and paste the audio in the folder.
I'm not sure if you have to create the same names as the folder name and the audio name, but that's how I did it.
Hope it works for you guys.
