I read somewhere that the tubes in the Millett would ring when you moved. I bought one.. it was true.. if you moved a lot with it - it would ring. I opened it up and saw the tubes were not really glued well onto the double stick tape. They sorta hung in space a bit...and could jiggle if you bumped it... like swinging a bit on the circuit board. So.... I thought.. what makes speakers couple well to speaker stands???? and stops vibration.....??? Blue Tack.. So I got some "fun taK" (made by DAP) likely the same thing... I took that little sheet of waxed paper that it comes with and made a ball of FUN TAK Then I folded the wax paper over on it.. And crammed that on top of the little tubes. It can't stick because of the wax paper but the wax paper made it slippery enough to slide back into its casing without moving.. and still maintaining gentle but constant pressure on the tube to keep it from vibrating. Voila... ZERO ringing...NONE NADA ZILCH.. the perfect tube amp... ----Appplause.....- Very happy now.