I have the same problem with my OnePlus 7 (non pro version) and Ring Doorbell Pro.
Gives horrible loud robotic distorted sound when the mic is enabled in live view either from the Full Ring app or the Rapid Ring app.
Works perfectly fine though from my wifes Google Pixel 3a and my Windows Laptop with the Windows Store Ring app.
Obviously a problem with Ring compatibility with the OnePlus 7.
I am very keen to get this fixed ASAP obviously as my phone is the primary interface when I’m away from home.
Please let me know how I can help to troubleshoot and resolve the problem.