Country Super group Thompson Square has called off a number of shows because of vocal problems.

(AP) - Thompson Square have called off their concerts through Sunday because singer Keifer Thompson has vocal problems.

He writes on the band's website he's been suffering from a serious vocal condition and has been ignoring the advice of doctors to rest his voice. He says he didn't want to disappoint fans, so he'd do the shows and be silent offstage.

That hasn't worked, so Thompson is on complete rest through the weekend. He has apologized to fans and promises to make it up to them.