Samsung LE46A656 and Wii - Horizontal interference and/or "mode not supported" shown

[oceanclub]

Have resurrected our Wii from a few years in the attic and connected it to our Samsung LE46A656. Nothing has changed in the interim - it's still the same TV and the Wii is connected via component cable as before.
However I initially got a "mode not supported" message on the TV. Following a tip online I unplugged the TV and all HDMI connections, waited 15 mins, and reconnected.
The Wii screen is now visible but there is quite annoying horizontal static line or lines - on the main home screen a single horizontal line in the middle, if I run a game or app, it might be a horizontal patch.
In some cases when I run a game or app I get the "mode not supported" message on the TV, which only disappears once back at the Home page.
I'm wondering could it be a TV setting I inadvertently changed at some point or is it something else?
P.

 

[eloisetringers]

It could be your TV setting. Try also to check again your cable wires if its plugged properly.

 

[YesMatrix]

I personally encountered this but the issue is not with the cable wires. You just need to reset the device.

 

[scanswild]

Did you check if device is compatible with your Samsung LE46A656? Or how about the cable wires?