Very hard to say without knowing more about your app, e.g. how you are accessing the camera. If it's open source maybe you could post your source code somewhere.
int main(int argc,char** argv) { CvCapture* capture = 0; if( argc == 1 || (argc == 2 && strlen(argv[1]) == 1 && isdigit(argv[1][0]))){ capture = cvCaptureFromCAM( argc == 2 ? argv[1][0] - '0' : 0 ); } ... for(;;){ g_image = cvQueryFrame( capture ); ... cvWaitKey(100); } ... cvReleaseCapture(&capture);