I just purchased an AEBS (new model with 802.11ac). I'm using it with Comcast internet service using a Motorola Surfboard SB6121. I have a very odd and frustrating issue. The internet simply blips in and out. I have it set up with WiFi and have connected devices such as my iPhone, iPad, Mac Pro, and a Chromebook to it. I have the issue on all devices so I know it's not device specific. The network itself never goes away. When I look at the WiFi area on my Mac even when the internet isn't working it shows it's connected to the WiFi network. Also, when the internet is not working the green light is on and staying lit (not blinking) on the AEBS so it appears the WiFi Network part of it works fine. As mentioned it's the internet service itself that blips in and out. What I mean by this is it may come on for 40 secs, go off for 20 secs, back on again, and off, just like that. I have not timed it and that would be hard but it seems to be very regular, something like 40 on, 20 off, and it may not even vary at all. It's a very bizarre issue. I have also direct connected the modem via ethernet to my Mac Pro. I used it for several problems with no problem so I know it's not the modem. The only thing I can think of is I received a defective AEBS. I purchased it through Amazon and I almost contacted them to do a replacement and send this one back. Yet I'm hoping it's something simple with the settings. Now I have already done a factory reset of the AEBS and that did not help. Yet I'm hoping it's simply a setting that I need to modify or wipe out. Any idea of what's causing this or is it simply a defective base station? Thanks for your help.