Which box do you have so we can offer tailored support.
General things to try are disconnecting the box from the mains and then restarting the box.
Checking cables, reversing the hdmi cable or using a different hdmi cable.
Check for updates.
As a last resort, a factory reset should reset all apps.
Hope this helps. Let us know how you get on.
From the 29th of March our TalkTalk Community will move to peer-to-peer support and the TalkTalk team will no longer be here to support with queries. Don’t worry we still have plenty of ways to reach out if you need to speak to TalkTalk directly. For more details check out the link here:
How to contact TalkTalk Broadband - Help & Support.
