Sometimes the B4A Log goes AWOL on me still (although a lot less often than it used to). Always when under pressure to get stuff done, so I haven't had time to work out wtf is happening... I just change to another device, and voila! she is back. And when I later go back to using the non-logging device, usually a day or two later, it has righted itself somehow.
Then there was one time that I had two B4A instances running... no end of trouble for about an hour, until I realised the problem was not the router or wireless network. That was painful, but the good thing about pain is that it is an excellent teacher: I have not made that particular mistake again... ;-)