The Media Tile integration is more of a static or streaming image type of integration. MJPEG, the streaming format used as shown in your final screenshot, is basically just streaming a series of JPEG still images as video, so it fundamentally doesn’t include audio.
–
There’s also an alternative approach where you can embed the Blue Iris UI3 dashboard directly into a Custom Tile. That lets you take advantage of all the features of the UI3 dashboard including rich modern streaming options, audio, etc. The tradeoff being that it’s enclosed in a Custom Tile so you can’t tap to get a large overlay (not sure if the standard fullscreen works or not)