buddy i had the same problem. i used it for one week and then it went dead.
Then the next day it started up itself.
So what i tried was:
- removed the update files from both of the dash
- inserted new files after downloading them from bragi.com
- followed exact same process as given for the custom update
- charged them full and kept them out of case for 18 hr(approx)
The next morning the were fine .
It worked for me I hope it helps you too