Once this starts happening, that error doesn’t seem to impact the normal operations of the device (at least not video), but sadly the error pops up quite regularly. It also associates to another message “Unfortunately, Launcher has stopped” every time you switch applications.
Some people have suggested to go to Settings > Apps > Running , and to force stop the “google services” app, which works for a little while, but it seems that service restarts automatically regularly, so the error appears again after a few hours.
The long term solution which was suggested to me and that I confirmed to work, is to update the Firmware to the latest version. Thankfully, updating the firmware is dead simple, I explain how it’s done here.
Updating my MK802 III o the latest firmware was a 5 minutes process and got rid of the “android.process.acore has stopped” error for me!