I've found the problem and fixed it. I'm 90% sure. I just gave the cable a mighty tug in several directions and no problems encountered. AND I learned something that is going to make the 880 VS 990 comparisons even weirder.
1. The problem appears to be the OFC cable. It is braided, or twisted, and very near to where it exited the cable inside the phone, it had partialy unbraided on the green conductor (left + ) which was causing it to rub against the center ground. OFC has it's own paint like insulation but it is also encased inside of a plastic insulator inside of the cable. Where it exits the cable inside they have stripped back the plastic insulator so that the 1" or so from the cable grommet to the driver, it's bare OFC wire. This shouldn't usually be an issue because of the aformentioned paint like insulation, but when it unwound it must have abraded a bit.
I simply re-positioned the driver so that the tension on the OFC wires would force them apart instead of together.
2. The construction of the wire is more robust than I had feared. There is a thick rubberized plastic grommet where it enters the headphone housing, this takes all of the strain of the weight of the cable and tugging/pulling. However, the coiled cable itself is free to move about a fair amount so that the conductors inside of the cable may sometimes slide inside of the coiled insulation, meaning it is possible to move the cables inside the headphone to a small degree by stretching or twisting the exterior cable.
My conclusion is that you can bomb proof these headphones by applying a little bit of nail polish laquer to the OFC where it might come in contact with other OFC, or using a little heat shrink tubing, wrapping them in paper, anything to help them insulate from each other.
And the bombshell....I think that the 880 and the 990's differences might be the enclosure and that they may share the same driver.
The 880 has a 1/4" thick felt pad that rides directly on top of the driver enclosure. It sits dead center in the middle of the paper that covers the enclosure.
The 990 has only paper. This is probably why it's top end seems a little more forward than the 880.
The 880 also has some felt like material inside of the exterior housing just underneath the outside grill. It looks like a felt donut that runs around the outside circumference. This likely attenuates the bass frequencies to some degree and leads to the 'semi open' sound and the flatter bass response.
The 990 has no such padding, it's open on the other side of the driver under the grills.
I would have to remove the driver from it's panel in order to be sure, but given the incredible symmetry between 880 and 990 on frequency charts, and their similar sound, I strongly suspect that they are in fact the same driver in different enclosures.
This means that if you add felt to a 990 you can turn it into an 880. If you remove the felt from the 880, you can turn it into a 990.