MP3 Used to play in WhatsApp, now Podcast Addict wants to play it Because my front mic don't work, I have to create an MP3 from the back mic, and send it in a Whatsapp message.
Sometimes I would click it to play it back myself.
It played in Whatsapp just fine.
Then I installed Podcast addict and now when I click on the MP3 in 
Whatsapp, it opens Podcast addict and wants to play there. 
I could not find where permissions got changed.
I want to keep Podcast Addict, but I want an MP3 that is in Whatsapp
to play in Whatsapp.

Any ideas would be appreciated.
Thanks
Go to the newly installed apps preference in settings, their will be a "set to default" kind of section.
Reset this for the new app.

This will reset defaults without removing the app, now you can open mp3 in your preferred application.