problem with ear 834p..... HELP

I am confused, baffled, mystified but most of all concerned. I recently replaced tubes in this phono stage and was very happy with the results. however after two nights of listening i put on the new Derrek Trucks band lp and noticed a considerable difference in volume levels between the two channels.figuring it might be a tube issue i was advised to switch the two outside tubes around to verify the problem (sound reduction would change to other channel w/repositioning of tube)alas it didnt i replaced new tubes with the tubes i had in before and everything was fine. So i thought if i replaced each old tube , one by one,. with new tubes i could identify the bad tube. I replaced the rear tube w/ a new one and again had reduced volume in right channel, eureka, problem solved i had found the bad tube, i thought. i replaced that tube with one of the two remaining new tubes and all was fine i had isolated the bad tube. so i put the last of the 3 new tubes in the front position and to my bewilderment I again had a reduction of volume in the right channel. Now what? what is the possibility of being sent two bad tubes by a very reputable dealer..... none. so i switched the two new tubes front to back and there was no change. The volume reduction remained with the right this point i was even more confused then u must be reading this. so i called the company who i had bought the new tubes from and ordered three new tubes with the agreement that i would send back the old tubes to be checked and compensated for if they were faulty.Fine, very professional, as this company always is.That is where the problem really began. i put the old tubes back in and played an lp & it seemed fine.I took the album off and was replacing it in the sleeve when i heard air coming from both speakers...... not normal.So i completely disengaged phono stage from all equipment and checked cd playback all seems ok there, no escaping air from speakers. My question, what have i freaking done? seeking any and all advice, associated equipment:sota star sapphire turntable with koetsu rosewood cartridge retipped by V D Hul, DK Design VS1 reference Mk 11 integrated amp. Sony scd 77 es cd player and Von Schweikert Vr-4 Gen 111 hse speakers. thanks in advance
did you see any bright glow on the tubes?
was there any glow in them at all to indicate they were still alive if not well?
New tubes can be affected by shipping hence the usual 60 or 90 limit on a warranty.
Can you even see the tubes in your phono preamp when on.? have not seen yours in operation so do not know.
Do you or an audio friend(fiend?) have access to a tube tester?
I am only guessing here but it seems to me that it is not the tubes but your Era causing the tubes to go bad..Its very possible that you need to have your ERA checked to find out if theres an Internal issue causing your tube failures.............
I doubt that your EAR is causing tube failures. I use one, and I find it to be very stable; but you never know. First of all, what tubes did you replace, and what did you replace them with (brand)? What you describe doesn't sound particularly unusual to me. I have experienced similar "mysteries" with tubes many times over the years that I have owned tube equipment. Interestingly, never with the EAR. My experience has been that no, it would not be terribly unusual to get two tubes out of three purchased that have section inbalance. As far as the old tubes getting noisy "all of a sudden", again, not terribly unusual when you consider that you where probably turning your EAR on and off much more often than usual, and perhaps with little time in between turn off and on. I find that tubes, particularly aging ones don't like that very much.

For the record, I have gotten the best results with Telefunken 12ax7's and GE 5751's in my EAR.

Good luck.
I would once again like to thank all who have read and responded.I took the ear to a local electronics "hobbyist" who is going to go thru the unit and check capacitors resistors etc. and check tubes. should know in a few days.Frogman,i see u have been there lol,u hit it on the head. That was a concern of mine and is why i asked"what have i freaking done" In regards to your tube recommendations are theese new tubes or nos? also what do u think of the new mullards as those were also recommended.
Hello! I know this thread is several years old but if the original poster sees this, I'd be grateful for a reply!

I've been having what sounds like the exact same problem. Volume imbalance with the right channel being quieter. What conclusion did you come to on this? Were you able to fix the problem?

Many thanks!
I’m having this exact issue, though only with the MC setting. Did anyone ever isolate the issue?
 Thanks in advance!