Firmware updated EX8000 keeps dropping Internet

Run as fast as you can from this product.  Tried two of them, all the same problems as listed above.  Spent over 4 hours on the phone with support on 4 different phone calls.  Support is obviously not in America and the techs are hard to understand at best. Becasue I have limited cell signal my phone connects via WiFi calling. I explained this to the tech and let them know that when the router or externder was rebooted, they could not call right back as I would not get the calll. 3 different times this happened and 3 times they called back immediately only to leave a message and force me to play the on-hold game again (never less than 30 minutes).  One tech had the gall to tell me to just call back and I would get right in. Yeah, right!  On the final call, I explained the situation and asked to be elevated. The tech kept probing.  Again asked to be escalated. Finally put me on hold for 5 minutes only to come back and say no manager was available to escalate to. At this point I hung up, returned the product to Best Buy and will try some other product.  Too bad because the router is nice and seems to work well.