Panasonic Viera TC-P50U50 Owner's Manual page 24

To use all ViERA Link functions: After everything is connected, in VIERA Link settings menu, set "VIERA Link" to "On".
Some features are disabled depending on the "HDAVI Control" version of the equipment.
Please check the list (p. 22)
Select "VIERA Link settings"
Set "VIERA Link" to "On"
Select and make other settings
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