It may be that where your Apple TV is located in your home is not getting a strong enough Wi-Fi signal (bandwidth). Please do not confuse bandwidth with Internet speed, 2 totally different things. Speed of the signal means the speed that your ISP delivers to your modem coming into the house, bandwidth is how strong the signal is throughout the home. There are many things that affect the signal's bandwidth including:
- How many floors in the home.
- Contruction type: i.e. wood frame, metal, Brick etc...
- Square footage of the home.
- The number of Wi-Fi devices on your network
So the first thing to do is to measure the signal strength where the Apple TV is compared to the signal strength where your router is. You can use a tool such as iStumbler to measure the signal strength. You may want to begin researching Mesh networks and see if you may be a candidate to upgrade your home's network.