Has anyone else noticed input lag when playing Virtual Console games in the Wii mode of the Wii U?

For example, on Super Mario World it takes ~0.3 sec between pressing the jump button and Mario actually jumping, which makes the game almost unplayable.

I have a new Samsung UE40ES6800 LED TV running in PC mode. The Wii U is connected by an hdmi cable. I measured the input lag of the TV using the gamepad and a camera (see Use the gamepad to test your HDTV lag - Wii U Forum - Page 1) and the TV is only lagging behind the gamepad by 1 frame (17 ms) in Wii U mode, so that is fine.

Normal Wii games also seem to work fine in Wii mode, only the virtual console games have this game breaking ~300 ms lag.

Most virtual console games suffer (those in 50 Hz), but a few work OK (those in 60 Hz). For example, those that don't work are 50Hz games like Super Mario Bros (NES), Super Mario World (SNES) and Super Mario 64 (N64), but 60 Hz Super Mario Bros 2 Lost Levels works fine.

When I fire up the Wii mode, the text in the top left of my TV says 1920x1080 @60Hz. When I start up one of the offending VC titles the text changes to 1920x1080 50p. What is this 50p? Why doesn't it say @50Hz?

What is my TV doing with this input that is resulting in so much extra lag?

I am coming to the conclusion that this may only be a problem for UK/European/Australian virtual console games running at 50 Hz.

I shall try my Wii U on some of my friends' TVs to see whether the problem is with the TV.

Any thoughts from anyone? Many thanks!