Disclaimer- I've spoken to both Klaus and Alex on the phone! I'm just looking for suggestions before I make the next step. I will likely be in contact with them again.
I have the Candela. I was noticing that my system sounded imbalanced and swapped cables around until I narrowed it down to the Candela. So, I emailed Klaus and he asked me to swap the tubes and see if it changed sides. It did, in fact, change side. So, I ordered the tubes that Klaus had recommended here (Northern Electric?) and paid extra for the tested/balanced tubes. Put them in and it sounded unbalanced!! Swapped them and it swapped sides!! Out of frustration I left the room and left the Candela on. When I came back to it the next day, it sounded amazing. And then over time it became unbalanced again.
Talked to Alex and he insisted that the tubes either work or don't and I have a contact issue. He told me to clean all the contacts with a special cleaner, and I did. He also wanted me to try the original JJ tubes, which I did. I still have about a 3db (measured) difference that swaps sides if I swap the tubes. Which points to the tubes but seems impossible based on 2 sets of tubes, one of which is new and supposedly balanced. And, Alex insists that it is NOT the tubes. So WTF?
I'm obviously frustrated. And just want to enjoy my HiFi. I'm about to the point that I'll get another pre-amp and send this in to Klause and see what is going on. And then decide what is going to live in my system after that. I honestly insist that the Candela made one of the biggest differences in my system that helped me enjoy listening to music (and not my equipment). But, now I'm tired of fooling with it.
So, any suggestions before I do something radical? I did think about getting yet another set of tubes; there have been some affordable ones suggested here. But that seems like throwing good money after bad based on what Alex has said.