Preamp cutting out on left side

You reseated all the tubes? 
Personally I don’t fool around with high end audio equipment. With the exception of tubes. I would call the dealer and ask his advice. I haven’t heard a tube fail this way, but I have had few problems with tubes. If you got from a dealer, he should lend you a preamp while it is being repaired 

Fix it  asap.

Yes it follows the interconnects …i reseated all tubes and it seems to not acting up , but I would guess just a matter of time 🤷🏻‍♂️ Thanks guys