I've made it a point to take a good look at ALL of the large miners I've recently purchased. All 4 of the 60ghs Avalons I received in 10/2013 had loose screws on the hashing modules. ALL of the Antminers S1's I've received over the last few months have all had loose screws on the hashing modules. I wouldnt be surprised if something came loose in shipping on these CT's. You might want to check that out.