My original UE900s were from the bad batch, RMA'd them for a new pair, which seemed fine in the beginning. I have noticed that after a few days one or both earpieces begin to experience the same issue, with the sound cutting in and out. Removing and reinserting the cable seems to resolve it, but it always comes back.
I will probably RMA them again, as they might have given me another bad pair. Having to re-seat the earpieces on the cable once or twice a week isn't a big deal, but I suspect the problem will eventually get worse, and, for $400 + tax, I have zero tolerance for such issues - especially since I have no such issues with my Sleek SA7s, or any of my cheap and crappy IEMs.
Logitech really needs to revisit this design, because I am convinced the flaw is in the new connector, and I would like to see a redesigned cable that addresses the issue permanently.
Also: the memory plastic on the cable is a joke. Seriously, this has been done well by so many manufacturers, there is no excuse for memory plastic with limited "memory". It utterly fails to remain tightly wound behind my ear for any reasonable length of time.
The IEMs themselves are divine, and at less than half the cost of Shure's new reference ridiculousness, a steal.