Q: I have to constantly restart the rental to play it - Internet connection is all excellent - is this a bug?

Something in this support article may help you >  Get help playing or streaming content on your Apple TV - Apple Support

Intermittent problems are often a result of interference. Interference can be caused by other networks in the neighbourhood or from household electrical items.

You can download and install iStumbler (NetStumbler for windows users) to help you see which channels are used by neighbouring networks so that you can avoid them, but iStumbler will not see household items.

Refer to your router manual for instructions on changing your wifi channel or adjusting your multicast rate.

There are other types of problems that can affect networks, but this is by far the most common, hence worth mentioning first. Networks that have inherent issues can be seen to work differently with different versions of the same software. You might also try moving the Apple TV away from other electrical equipment.

The following article(s) may help you.

Troubleshooting Wi-Fi networks and connections

Recommended Wi-Fi settings

Sources of Interference

Wifi Diagnostic Software (for Mac users)

You may also find some help on this page, where I’ve collected some of the more unusual solutions to network issues.

What is your current connection via speedtest?

Make sure DNS is set to auto (settings - general - network)

If on wifi try ethernet

To see a current status of the network get a report from istumbler, netstumbler or similar. Look for signal strength, noise, nearby networks

Test on another network

If you leave the rental paused for a few minutes, does playback last longer?

How fast is your internet connection? You can use speedtest.net from a computer or iOS device(via the App) to test your connection speed.

Sounds like your download speed is not fast enough to keep up with playback. ie it cannot download enough movie to play before it needs more, and so it stops playing since it has no more movie to play. Then it has to wait until enough is downloaded again to continue playback.

Remember it may be good enough for websites, and video services that adjust video quality to fit connection speed such as Youtube and Netflix, but iTunes requires a steady connection since it does not adjust.

If you are watching HD movies from iTunes it requires and even larger and steadier bandwidth.

Above 8mbps is recommended for iTunes.