6H30 tubes ringing in BAT VK-300SE


I have had this issue in nearly every 6H30 tube I have bought for my BAT VK-300xSE integrated. Whenever I switch inputs, or the unit comes out of warm-up mode, or out of mute, I get a high pitched ping followed by a ringing sound out of the speakers.

I have tried 3 different sets of tubes- two pairs of Electro Harmonix gold pins, and one set of Sovteks. Eventually it gets to the point where if I tap on the chassis of the BAT, I get the high pitched ping/ringing out of the speakers. The last new set of EH's I bought, when I pulled them out of the box brand new, and tapped on the side of them with my finger, bingo- it audibly rings in my hand!

It doesn't seem to affect the sound, but none the less, are there any good sources for QUALITY 6H30 tubes? I am not going to pay $300-$400 for a pair of the "New old Stock" DR tubes. I have bought all of the Sovteks and EH's from Music Direct. Maybe they got a whole batch of bad ones?

Please Help!!!
Ag insider logo xs@2xmekong56
That's just a microphony, which is inherent to many types of tubes, and there is little you can do about it, no should you. It doesn't affect the sound, and only happens, when the tube is mechanically "disturbed", when you switch inputs, for instance. This is not a problem, "part of the package".
Thanks for all of the responses. Good information here. Seems like I have confirmation on what I was suspecting- it is a tube issue, but live with it as it does not seem to affect the sound. I was more concerned with getting feedback from other BAT owners that it is NOT a problem with my integrated.

I do very much enjoy the BAT sound. I guess that it is just more of an annoyance than anything else.
Thanks JFresh hadn't plan on rolling tubes but did consider investing in tube dampers. However was hesitant since I did feel it would be a waist of money. My dealer also warned me that this is a quirk of BAT Pres it is nice to hear that this is normal part of owning BAT gear. Which in my IMHO makes some of the most relaxed and natural sounding preamps out there.