Right channel phono stage tube goes noisy

When I swap the left and right channel tubes, the noise goes to the left channel.

@earthtones This statement suggests that the tubes you installed in the channel in question were in fact defective.

I've never seen a fault that could cause a tube to go crackly like this. So IMO/IME the simpler explanation is you've had bad luck putting the bad tubes in the same channel.

Swap a known good tube from the good channel and see if that goes bad. Then you'll have your answer.

That’s a tough one, and I don’t have any ideas beyond what’s been posited by others. Just wanted to say I’ve encountered more gremlin-y issues with 6922 / 6DJ8 tubes (and sometimes the components that use them) than any other tube type. F that tube type lol. 6H30 is better anyways for line stages, 6SN7 for drivers (or perhaps even better 5687 / 6BL7 / 6BX7), and 12AX7 for RIAA phono stages.

Of the 6922 tube variants, I’ve had relatively better luck with Siemens E88CC and Japanese Matsushita 7DJ8 / PCC88.

You want to drive yourself crazy, get a DIY T2 (extremely complex EL34 hybrid electrostatic headphone amp with +/- 500 Volt rails) with its 6922 quad on the input stage.

Thanks everyone, for the advice. The dealer is sending me a new replacement phono preamp, so I didn’t have time to try that left to right tube swap. But I will if it happens again. I was not aware of all the troubles with the 6922. I used to have a PS Audio BHK preamp that had them, which gave me no problems. I substituted a set of NOS Amperex 7308s, which were fine and that I would buy again, but in that unit, I had to flip a switch to change the bias voltage. I’ll have to find out if there’s any such compatibility issues with this unit, which doesn’t have that switch.

“That’s Odd??? Self healing tubes? What happened when you tried the tubes they tested back in the phono preamp?”

They said the tubes tested fine. But I’m quite sure they didn’t listen to them in my preamp, which I had sent to them. So, yeah, I’m confused about that. So I’m stuck with four pairs with one in each pair that’s of course still noisy.

After having the brand new replacement phono stage on for about a day, incredibly, the right channel MC stage 6922 went popcorn noisy! This is the fifth time in a row! I swapped tubes, and as before, the noisy sound went to the left channel. For just a moment, put aside this specific case and consider flipping a coin five times and it lands on heads each time, or tails each time. The probability of that happening is only 3 percent. Now, take away from that whatever likelihood that a new tested tube goes noisy, say within 24 hours. Afterall, this is an electronic device and we're not expecting it to fail so soon. Further subtract that's it's just one side. I don't know what that chance is, but combined, it must be very low. But, it happened to me. Now, in spite of it being very tempting to more heavily favor the idea that there is a problem with this circuit design or execution (like a bad resistor or something else, such as the circuit design driving the tube too hard), and considering the advice I got above, especially from @atmasphere   and @mulveling , I must now give more weight to the idea that I simply got incredibly unlucky. That is because I took the left channel tube and put it in the right socket, and I took one from my good stash of growing 6922s of a different brand and stated specs and put it in the left side. I've had the unit on for a about a week straight, and... it's remained quiet! Also, the first time I had this issue, it wasn't untiI I owned the preamp for about six months that the right tube went noisy. Also, I can't find anyone else who has had this problem. One thing I'm tempted to conclude, though, is that all of these bad tubes of various brands came from the same vendor, who I wonder may not be testing them correctly. They're almost certainly not running each unit that is sold for say, a week straight to make sure it's still good. Going forward, since I desire a precisely matched pair, upon Andy Bowman's recommendation for a set of very tough and good sounding tubes, I've ordered a set of Matsushita 6922s. 

I'll be damned if that right side goes noisy again any time soon!

Furthermore, this all sounds like it may be an indictment of the 6922. But plenty of gear runs these tubes. My PS Audio BHK 600 pair is just one example. I haven't had any problems. Granted, this is in the driver stage of an amp, not a highly sensitive to noise MC gain stage.