If you use Ethernet cable to connect and dont need Wifi, here is a link to Firmware I Installed yesterday.
Brings the M8s back to Android 4.4.2 and seems to function in all areas except the wifi chipset "for my unit" is different than the Code.
https://quickfileshare.org/vw/M8s_2017.zip
Zip file includes a zip file and 2 other files
Unzip the 2 files + the zip file (but dont unzip this file) onto a blank SD card.
Remove power.
Insert SD Card.
Insert pin into A/V port (reset switch inside) - press and hold.
Plug in power and keep holding until you see the Logo disappear or about 10-15 sec after power up.
Let it do its thing.
I lost wifi though, but dont need it.
/kens
**** UPDATE *****
Unit worked great for 1 day.
Now Hangs at startup on a "Logo" -> TVUnlocked
Attempted to ReFlash and the startup procedure is no longer recognized ???
* Use at your own Risk */kens