Blacking out and then coming back could be one of many problems. For me it's usually a "handshake" issue of some kind, caused by a bad/flaky or dirty cable or HDMI Ports. It also could be a bad/flaky TV or MIBox.
I had issues when trying to use 4k, but things cleared up when I just went 1080p. I also noticed that some cables worked "better" than others, also I have had more issues with older cables than newer ones, but usually they don't really have any issues until I try to push 4k though them.
As weird as this may sound, have you tried reversing the cables? Also, plugging the cable into the HDMI port a few times in a row can also help at times, as the action helps to "clean" the connectors contacts.
You did mention trying different cables and using different ports on the TV, to no avail.
The thing you didn't do was to try another TV, which would help rule in/out your TV and or MiBox. A TV with a intermittent or failing main or interface boards could have symptoms like this. If you don't have a second TV set, then it might be worth the effort to take your MiBox to a friends.
You also could try setting the video to 720p to see if that makes a difference. Lower resolution is better able to get through a crappy/flaky cable.
When the screen goes black what happens if you try to adjust the TV's volume or bring up a menu for the TV? If they don't work I would lean towards the TV having an issue, but sometimes a TV won't show on-screen display when it's switching or stuck while switching modes...
I think this is all I can come up with, for now...
I do hope that you are able to find a solution to your issue...
Good luck!
BiggussDikkuss
Purple Green distortion = incorrect colorspace handshake between the TV and Media Player.
Old Sony / Philips TV's are notorious for causing this problem.
Suggestion in Android Display settings set output to RGB.
Blacking out and then coming back could be one of many problems. For me it's usually a "handshake" issue of some kind, caused by a bad/flaky or dirty cable or HDMI Ports. It also could be a bad/flaky TV or MIBox.
I had issues when trying to use 4k, but things cleared up when I just went 1080p. I also noticed that some cables worked "better" than others, also I have had more issues with older cables than newer ones, but usually they don't really have any issues until I try to push 4k though them.
As weird as this may sound, have you tried reversing the cables? Also, plugging the cable into the HDMI port a few times in a row can also help at times, as the action helps to "clean" the connectors contacts.
You did mention trying different cables and using different ports on the TV, to no avail.
The thing you didn't do was to try another TV, which would help rule in/out your TV and or MiBox. A TV with a intermittent or failing main or interface boards could have symptoms like this. If you don't have a second TV set, then it might be worth the effort to take your MiBox to a friends.
You also could try setting the video to 720p to see if that makes a difference. Lower resolution is better able to get through a crappy/flaky cable.
When the screen goes black what happens if you try to adjust the TV's volume or bring up a menu for the TV? If they don't work I would lean towards the TV having an issue, but sometimes a TV won't show on-screen display when it's switching or stuck while switching modes...
I think this is all I can come up with, for now...
I do hope that you are able to find a solution to your issue...
Good luck!