There is no TalkTalk TV as such.
Which box do you have?
If it's the Hub or 4k box these are both WiFi enabled so will work. You need the internet to access catch up apps.
Using ethernet will improve stability if you experience issues playing apps via WiFi.
Earlier YouView boxes need to be plugged to the router, either directly or via power line plugs.
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.
