Call garbles Audio

Hello,

I have an odd problem. When I make an audio or a video call from a particular PC using whaysapp, the other end comes out completely garbled. They can see my video just fine but cannot decipher anything that is being said. Zoom works just fine so I know the audio and the networking machinery works. WhatsApp help was not much use at all. 

Any help?

Kindle Fire / Silk 118.1.77