Because this thread comes to the top on the google search.

The problem is your HDMI port, it has to be 'HDCP compliant'. On some TVs only one port in HDCP compliant. On Vizio is marked as 'Best'

HDCP is copyright management protocol.

I know this is an old post but I found a solution (for me at least) while digging around Google. Go into your settings on the MiBox, go to sound settings, change your sound settings from PCM to auto.

I found this solution on a Nividia shield post. For some reason it worked. Hope it works for you!

I had this error on my shield quite a bit before I did a factory reset. None of the troubleshooting ever helped. I had a suspension it had something to do with adding extra storage but I don't know much about the mibox.

was Netflix working before?

Reboot after powering on. It's because of hdcp 2.2 switch to unprotected. BUG

DRM issue.... dowload DRM info and check google widevine drm, if it is unprotected then your device is defective.

I just had this problem after my box updated to the latest software. Netflix app also updated.

Here's what I did:

Un install update on App. Didn't work, upgrade again.

Chose auto instead of pcm on box audio settings.

Found out it could be because of my hdmi, so I use a different slot on my hdmi splitter.

Then made sure my old TV can play 1080p, though it has 1 hdmi port I found out there are input 1 n 2, one is 480,the other 1080. Head to box setting, turned off the "use TV setting on video quality". Note that I can play HD even before this on Netflix, via my laptop and on cable TV ex. HBO HD.

Tried again and it worked, no more error prompts. Now I don't know which of these things I listed made it work so Goodluck.

PS I had thought of not updating my Mi box when the notification to update appears because I had no problems with it. Turns out I was right. I should have ignored it. Good thing I worked it out.