Odd Strum Bar

[Sero]

So I got Rock Band on the XBox 360 and somethings very weird about my guitar. Whenever I hit the note it says I hit the note but then my bar on the left goes down. So every time I hit the strum bar once it says I hit it twice or maybe three times I'm not sure.

Is there something wrong with it that I can fix or am I just doing something wrong?

[Sero]

B
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P

[TribalDancer]

I am having this issue as well. In addition to general sluggishness of the downstrum. I am ordering a replacement guitar and hope it is fixed there. But wonder if this is addressed in any of the self-fixes I have seen online...