Guitar Hero III mystery

Considering I'm *old*, I think I'm pretty decent at Guitar Hero. I'm part way through solving the hard level in career mode. Kilr Bunez, FTW!

We have the game for the Wii and I'd only ever played on our own system until last weekend. Then Saturday night, we went to the neighbor's house to play on their Wii. Two guitars in face-off mode, lots of fun.

Here's where the trouble started. I sucked. I failed at easy songs in easy mode. Tink. Tink. Tink. WTF was wrong with me? Same thing happened two nights later. Something was seriously off with my game.

Everyone else played fine. In fact, the elementary-school-age neighbor girls played amazingly well (but then again, they play the real guitar, too). Apparently it was just me. Perhaps it was the television, we pondered. Perhaps I can only play on a 70-inch HD set like we have at home? (How spoiled is that!)

But then my moment of redemption came on New Year's Day. The neighbor girls came over and we played again. I was back to my normal self, cruising through a medium-level song, then plowing my way through a hard-level song (it's not pretty). This time, it was the girls who had problems. Tink. Tink. Tink. They missed note after note after note.

It's not me! Yeah! Instead, it's some difference between our Wii systems - or perhaps it really is the 70-inch HD television.

Has anyone heard of such a thing? Is there some known issue like this? I tried Google, but no luck.

On a side note: Thanks to Guitar Hero III, I now love, love, love "Miss Murder" by AFI, and my joy with "Cult of Personality" by Living Colour and "Cliffs of Dover" by Eric Johnson has been reaffirmed -- BUT, if I never hear or play "Slow Ride" again, it'll be too soon. ("Talk Dirty to Me" and "Hit Me With Your Best Shot" are becoming close runners-up. In fact, that whole first set is a little dodgy.)

BTW, my husband took the above photo the first day I had the game. I can't begin to describe how amused he was by my fascination with playing. :)