Why is my tablet restarting itself?

[AC Question]

I got a LG Gpad 7.0 LTE for free as a promotion from ATT. Told the lady I didn't want it on my data plan so she removed the sim card and now I use it on wifi. Any time I stream video (have so far had it happen with Netfliz, Twitch, and Youtube) it plays fine for about 30 mins then my tablet restarts suddenly without warning. I've done a factory restore once with no results.

 

[B. Diddy]

Welcome to Android Central! Assuming YouTube was preinstalled, try booting into Safe Mode and see if the problem persists while streaming on YouTube: Restart the Device in Safe Mode LG G Pad LTE 7.0/10.1 | Verizon Wireless. If the problem goes away, then some 3rd party app might be causing the instability.