Audio Files on Whatsapp Application has a special audio format which is called opus , and if you want to upload an audio file to Whatsapp web , you have to choose through the upload window which media you will use: Camera , Album Folder , Document or Contact.
Just use the Document option when you want to upload your mp3 file.
For more technical details about this subject you can visit this Thread
Just use the Document option when you want to upload your mp3 file.
For more technical details about this subject you can visit this Thread
