Airport Extreme not playing nice with Android

Ok, I am not the least bit savvy when it comes to anything networking. I will just tell you what I have and hopefully someone will have an idea. I have an older macbook pro, a few iPads, an iPhone 6s and a samsung note 5. Up until a few days ago I had ATT Uverse internet with their supplied modem/router combo. It always worked fine but was a bit slow. I recently upgraded to the local cable companies internet. I purchased my own modem, which is an Arris sb6183. It is not a wireless unit. They hooked it up, called it in and I hooked my macbook up to it to verify it was working. I was getting 120Mbps down, which was good since I am paying for 100. Anyways, after he left and I hooked my newly purchased airport extreme up and set it up via the airport utility. Everything worked great and I was getting 100 down over wifi. Sometime late that evening my speed dropped to a crawl to about 30. I reset the modem and it seemed to fix it. Today I discovered something that is very strange to me, and has left me clueless. All my apple products are working fine, but my note 5 is acting very strange. It has good signal, I can surf the web etc no problem, but it DOES NOT like "media"..for instance my pandora in no shape or form will open on my note. The app opens, but when I try to stream a song it times out. I tried you tube...nothing. The site itself opens, I can search for content, but when I try to play a video it just times out. Whats crazy is I can do a speediest via an app and I am getting 70-100 down, but it seems my connection is hit and miss. Even surfing the net seems to take longer than it should. It has to be something that the airport does not like with my note 5. I did read somewhere that once I connected to the macbook (first thing I connected to modem when it was turned on), that it creates a problem with passing data onto the router since that was the first thing i connected too. I reset both the modem and airport, unplugged all cables etc..Didnt seem to change anything. All the macs/iphones/ipads seems to work but my note 5 is not having it. I've did the obvious, reboot phone, etc etc. Ive never had a single issue out of it or the wireless. I had originally purchased a r6400 netgear router, but returned it and got the airport. I read somewhere that the airport did better with speeds on the 2.4GHZ, and my iPad and macbook pro are all older. The only wireless AC devices I have are the wife 6s and my note 5. I don't know what to do, its seems very strange the way its acting. If its worth anything, I think the web pages load slower than they did before the "upgrade", even on my macbook. I can see the speed test says its faster, but even going to say google, takes a few seconds and it seems to lag before it loads the page..any suggestions? Sorry so long.

Thanks,

Matt