Wifi Dropping Out iPhone 6

Had Apple gear for years. Everything worked well. Bought two new iPhone 6's to replace my iPhone 4 and my wifes iPhone 5s. My network at home is BT infinity so I have a BT hub 3 but due to wireless positioning I have a net gear access point which is my point of wireless connection and the bt hub wireless is turned off.

All was fine, when I turned on the second iPhone 6 after about 2 minutes or so both phones loose internet, sometimes other devices on my network are affected as well - Sometimes they are not! If I leave one of the iPhone 6's off my network all is fine. Doesn't matter which phone is off.

I've taken both iPhones to my work and used the wireless and all is fine. They sit there fine and work/play nicely together. At home I've reset all the ip's and turned things on and off to see if a conflict can be found. I've even brought home my wireless access point from work and replaced my net gear AP but the problem still occurs.

This means I've narrowed it down to the BT HUB 3. What is in the iPhone 6's to cause such a problem? Has anyone else had this problem? My iPads all with iOS8 on seem to work fine so either the phone hardware is causing a conflict or the iOS 8 with the hardware of the new phone is? Advise on how to fix or further testing options would be most appreciated. Are there any settings on the phones or router I should try changing? I'm starting to hit a dead end with any further ideas!

Robert