Home sharing movies from iMac to Apple TV stops intermittently

Hello kentmcpherson,

Welcome to Apple Support Communities. 

We understand that you’re concerned about your movies buffering. We are happy to help.

While you can use Ethernet, we recommend using the steps here to check for wireless interference: Resolve Wi-Fi and Bluetooth issues caused by wireless interference - Apple Support

How to reduce wireless interference

These general steps can help achieve a cleaner, stronger wireless signal:

• Bring your Wi-Fi device closer to your Wi-Fi router. Bring the Bluetooth devices that are connecting to each other closer together. 
• Avoid using your wireless devices near common sources of interference, such as power cables, microwave ovens, fluorescent lights, wireless video cameras, and cordless phones.
• Reduce the number of active devices that use the same wireless frequency band. Both Bluetooth and Wi-Fi devices use the 2.4 GHz band, but many Wi-Fi devices can use the 5 GHz band instead. If your Wi-Fi router supports both bands, it might help to connect more of your Wi-Fi devices to the 5GHz band. Some dual-band routers manage this for you automatically.
• Configure your Wi-Fi router to use a different Wi-Fi channel, or have it scan for the channel with the least interference. Most routers perform this scan automatically on startup or when reset.

Apple recommends these router settings: Recommended settings for Wi-Fi routers and access points - Apple Support

Router settings

To ensure that your devices can connect securely and reliably to your network, apply these settings consistently to each Wi-Fi router and access point, and to each band of a dual-band, tri-band, or other multiband router. Before changing the settings, you should take these steps:

• Back up your existing settings, in case you need to restore them.
• Install the latest firmware updates for your router. This is generally done from the app or webpage that you use to administer the router.
• Update the software on your other devices, such as on your Mac and on your iPhone or iPad, to ensure that they have the latest security updates and work best with each other.

After changing the settings, you might need to forget the network on each device that previously joined the network. This ensures that the device uses the router's new settings when rejoining the network.

Let us know if you have further questions.

Take care.

kentmcpherson,

Thanks for following up with us. You mentioned this happens with a direct ethernet connection, and also it sounds like the movies are stored on an external hard drive, correct?

To narrow this down further, we recommend copying a movie to your internal hard drive for testing purposes and then trying it out to see if that helps. This would be a good way to rule out read/write speeds on the external hard drive as a possible cause.

Let us know how it goes, and have a good day.

kentmcpherson,

Apologies for the confusion, we just want to rule out the read/write speeds as a possible root cause of the issue you've described. The best way to do so is by moving your library back to your internal hard drive and testing further as that's one less place for Home Sharing to have to work through to get to your files.

By default it would be stored under /Macintosh HD/Users/[username]/Movies/TV/Media, but it sounds like you've moved your library to an external drive instead. If you can move your library back to the default location and set that default location back as your Media folder location, test things out further and let us know the results. For more info, also check out: Change Files settings in the Apple TV app on Mac - Apple Support

If the behavior persists though, you'd be best supported by reaching out to Apple Support from here: Get Support

We hope this helps out.

Take care!