I think you have to get new clamps, this popping you're decribing is relatively common on those clamps, unfortunately, once it pops just once, you can kiss that clamp goodbye since the angled slits in the band will be bent now and weakened.
If you purchase the most expensive ones you can find, they can take more torque before popping. I'm not one to always buy the most expensive, but have found that when it comes to those clamps, more expensive is actually better.