WPE-Webkit-Mir-Kiosk locally hosted video and audio not playing

I am trying to deploy an application on Ubuntu core 20 as a kiosk. I am using mir-kiosk and wpe-webkit-mir-kiosk to display my application. The issue I am facing is that wpe-wbkit-mir-kiosk doesn’t play my video and audio files (mp4 and mp3 format respectively). Rest of the application is working fine. My application is running in two docker containers, one for the front end and one form the backend.

I have tried playing videos form youtube and both video and audio work fine there. I have also tried my application with mir-kiosk-chromium and works perfectly fine with it. There are no errors in the log and I cannot figure out what is wrong or where to look for the issue. Any help is much appreciated.