While streaming Invasion of the Body Snatchers (1978) I had CGMiner 4.9.1 close & exit twice while mining at solo.ckpool.org, I switched pools to bitcoind running locally and it's been going without exiting for about 30 mins now. I'm running the Windows build of CGMiner and it had been running for about 24 hours and only started crashing while watching the movie.
I haven't seen this behavior before, I just upgraded the miner to CGMiner from BFGMiner yesterday.
You've clearly run into that rare incompatibility between CGMiner, Windows and the streaming of a bad horror video on the same wifi network. Such unwelcome bandwidth harmonics only affects CGMiner 4.7 and higher. It is recommended that you downgrade CGMiner or switch back to BFGMiner immediately, or upgrade to Linux.
And count yourself lucky it wasn't a good horror movie. I bricked a whole stack of S4's binge-watching the Saw movies that way!
I streamed one of the Superman animated movies (low res off YouTube) last night and all the eruptors lit up again. I alt-tabbed out of full-screen to find the system had ground to halt, I even had no mouse action for a few seconds and CGMiner complained about lack of work but it didn't crash like while mining at solo.ckpool.org.