Streaming inside my home on my desktop using Firefox browser

According to Directv my package is supposed to allow me to stream to my desktop computer in my home and it used to work with no problem. But for the last several months in has been hit and miss as to when it would work and now it won't work at all. I am using Firefox and I have made sure I have Flash installed. Sometimes it will tell me I need to download the directv player which I have done many times but when I reload my browser and go back to directv it just goes back to telling me I need to download the player. Other times it will look like it is going to work but when I hit the Watch button then it will come up and tell me I need to check my connection and or something about computer and directv need to be on the same network. I tried calling their tech support and they didn't have a clue and said they would have someone else call me back but of course they never did. I have even tried using the Chrome browser and I run into the same problems. How can I make it work?