Problem with tube rolling 6SN7s

Question from inexperienced tube roller here (hopefully not a stupid one). I'm running a Rogue Audio Stero 90 power amp with 12AX7(2) and 6SN7 input tubes. The stock 6SN7s are Chinese and don't sound bad at all but I have a set of NOS GE GTBs that I wanted to try. About 5 min after I installed these and powered everything up it tripped the protection circuit in my power conditioner. Any thoughts?
One of the NOS GE's probably has a short in it. Once it warmed up, it kicked the breaker. You could swap out, one at a time, the GE's with a stock Chinese to find which one.
I have noticed that tube stuff sounds much better without a conditioner, but that is my experience with my tube buffers, have not tried it with my preamp.