Apple TV can deliver a world of digital video direct to your TV, but network problems that cause slow streams can be a major headache. To fix slow streaming on your third-generation Apple TV, you can make adjustments to its software, adjust your network or change the content quality of what you're watching. Apple recommends you have an 8-megabits-per-second connection for 1080p HD content, at least 6 Mbps for 720p content and a 2.5 Mbps connection for standard-definition viewing.
If your Apple TV is streaming slowly but your PC and other devices connecting to your wireless network are working properly, you may want to switch from a wireless to a wired connection. The third generation Apple TV features a 10/100BASE-T Ethernet port, so it can be directly connected to your router or modem. The Apple TV requires an 802.11a, g or n wireless network for video streaming, which an older wireless router may not support.
Checking Your Network
Sometimes your Apple TV isn't the problem, but your network is. Reset your modem and router by unplugging them, waiting at least 15 seconds and then plugging them back in to an outlet. Restarting these can sometimes improve the connection between your Apple TV and your network. You should also move any objects that may impact signal strength, such as wireless speakers, cordless phones and other devices that operate in the 2.4 GHz or 5 GHz bands.
Update and Safe Resetting
Apple recommends that you reset the Apple TV and check for an update if you experience repeatedly slow streaming despite a strong connection. To restart your Apple TV, go to the Settings option in the top menu on the Apple TV home screen. Select the "General" tab in the Settings menu and then click on "Restart." This lets you safely restart your Apple TV without having to pull its power cord. After it restarts, return to the General tab in the Settings menu. Click on "Software Updates" and install any available updates.
Switching to Standard Definition
If a slow or fluctuating connection causes your device to stream slowly, you can adjust the definition of the content you're streaming. For third-party services such as Netflix, Hulu or MLB.TV, you'll have to change the setting directly through those services. For content you stream from the iTunes Store or iTunes Match, you'll need to make changes in Apple TV's Settings menu. Navigate to the iTunes Store option and select "Video Resolution." Change this to either 720p or to standard definition.