We have 25 Mbps and can stream 3 TV'S at one and One iMac and on Samsung Tab or Pad??? We use a Roku. I had purchased the latest Firestick and sent it back because while all Roku Program worked fine the Firestick shows constantly buffered. I wish you luck bud, it can be frustrating.
We switched to a Motorola Modem which didn't really improve the performance but knocked something off the bill. It's $19.99 until June or July with Comcast.
I'm just kidding now, IT'S BECAUSE YOU ARE SO FAR AWAY THAT THE INTERNET IS SLOW. THE PEOPLE IN BROWNWOOD ARE GETTING ALL THE FAST INTERNET. IT WILL BE BETTER ONCE THE NEW BRIDGE IS INSTALLED!