I have an issue of my own, though. I need to do something about a resonance at sub-bass frequencies and popping noises (the so-called "Stax fart", perhaps) in the left driver (but NOT the right driver, which sounds fine). I think it's because whoever rebuilt the drivers before I got them didn't quite glue them on right between the driver (which looks like there are uneven half-millimeter gaps and generally non-flush fit between the driver, protective mesh, and mounting plate in some places). The right driver shows a flush fit all around.
The resonance goes away if I press down a bit on one edge of the driver's rear (which doesn't visibly close said gaps and uneveness) or the protective mesh and just gives clean sound, which leads me to think that the diaphragm, spacers, and stators are fine, just not what the whole driver sandwich is attached to. As for the popping noises, I can't hear them if I remove the pad on that side and put them on, or leave the pad on and press it in with my fingers, as if it only happens when it has a seal with my head. Again, none of this affects the right driver, and I know it doesn't involve the earcups because the resonance still happens with the left driver when removed, and the pops come back if I switch the left and right drivers so they're mounted in the opposite earcups, with opposite earpads.
I just don't know how I'm going to separate everything safely, without breaking anything, much less mounting it properly so that the resonance is gone...aside from that driver mounting issue, the SR-Lambda sounds great, and I certainly don't want to be without an electrostatic headphone from here on out!