Somehow, somewhere, a big hunk of crap got lodged into the viewfinder optics and it doesn't seem to want to come out. I know it's not on the sensor because the pictures are crystal clear. I tried gently shaking it in different directions, and used the blower bulb in case it was on the mirror, but it doesn't seem to be. The thing is just not budging. Any suggestions? I'd rather not send it back. Thanks.