XIAOMI MI BOX No Sound

Step 1: Click the MENU button on your XIAOMITV remote and go into the Gear Icon

Step 2: Scroll down and select "Device Preferences." 

Step 3: Scroll down and Select "Sound."

Step 4: Scroll down and Go into "Digital Audio Format."

Step 5: Set it to "PCM."

Step 6: Go Back to "Sound."

Step 7: Scroll to "Dolby Sounds" and switch it to OFF.

Step 8: Adjust Settings on your Actual TV (Samsung, LG, Sony... etc.)

Look them up by Brand.

If you prefer Learning through video, this should help: