You can now add audio files to your pages very easily with the new Audio Player element. This element was released in the OP Builder plugin version 1.0.40 on January 28th, 2021. If you do not see the element available, just make sure you are using the latest version and you should see it.
You may read more about this element on our website at https://www.optimizepress.com/features/wordpress-audio-player/
If you need any help with using the Audio Player element, please reach out to our helpful support team.