I’ve been having the same problem, and ironically enough am in NJ and use fios. I’ve done everything including a factory reset. It started becoming a serious problem on Tuesday, now it’s unplayable.
I just now as I am typing this was locked out with the grey screen. I logged off bnet and turned OFF my anti-virus. I logged in just fine now after doing so, it has worked as quick fix. I don’t know for how long though seeing as I was able to play for periods at a time before this became as persistent to the point it did. Going to try and run it for an hour or two, will update.
Yeah: that worked for maybe an hour… short lived at best