Wii Rock Band 2 guitar not registering notes?

I've recently acquired Rock Band 2 for the Wii. I've been playing the guitar on a medium difficulty setting, and it seems like something is really wrong with the controller properly registering notes. I am a musician in real life, and was in band through school for 8 years.....so I would think I could hit a note/notes accurately on time....however, a lot of my notes don't seem to be registering in the game. My battery tester shows the batteries seem to be ok.....and I have tried auto calibration.....I am using a regular og TV though. Is there something else possibly going on? I can't suck that bad having the musical background I do.