Guitar hero world tour guitar motion sensitivity problems

[thebandz]

On guitar hero world tour my guitar is normal, when you lift it up, it uses star power, if you don't, it doesn't. However, when I use the same guitar on smash hits, star power goes off immedietly after I get it, I think the reason is I hold it slightly up when I play, because when I sit down it's totally fine, and I don't like sitting down cuz I have to crack my arm every couple minutes. anyway is there any way to fix this?