Topic: Weird control issue in Sonic the Hedgehog VC title

I've played Sonic the Hedgehog (Genesis original) many times, and don't remember having issues controlling the height of Sonic's jumps. That includes playing the Wii VC version. However, recently when playing it on my Wii U (via Wii mode), his jumps are very erratic and hard to predict or control. Standing in the same spot and hitting (and holding) the jump button repeatedly causes Sonic to jump anywhere between his full height and half of that. It's almost as if the controller is losing contact with the system so the game thinks the button is being released early. However, I have tried 2 different Wiimotes with the same results.

Does anyone else have this issue, or is it just me? I'm worried that there might be something wrong with the console, but no other games exhibit this type of behavior so far.