Just sent in my second pair of UE900s as these were also cutting out.  I haven't followed this thread for a long time, but has the cutting out issue ever been solved?   I received my second pair back in October and they have always cut out as well, but I just learned to deal with it.  However...

Well, I'm experiencing the audio cutting out of my left driver on my 1-week old UE900s despite which cable I use.  I've tried re-connecting the ear bud several times, and so far no luck.   Just logged a ticket with Logitech, as I couldn't get through their 646-454-3200 number for some reason...

I left my UE700s in Cabo recently and got the UE900s to replace them this week; having access to 50% off of Logitech products makes it a no-brainer :)   I will be pairing them primarily with my iPhone 5 and was wondering if using the Accudio Pro app with the UE900 profile and simulation mode...