XPS 13 BlueTooth bttray.exe breaks iTunes

Agreed. It certainly could be an Apple created problem. But the conjunction of (some versions of?) WIDCOMM BT code and iTunes causing this problem seems very narrow. (I.e., why doesn't anybody else's BT software break iTunes?)

The other thing is that when it comes down to a piece of software used on two or three hundred million machines or one used on maybe hundreds of thousands of machines, the little guy is always going to have to fix it regardless. Even if Broadcom is right and Apple is wrong, Broadcom loses. (Actually, mostly, people like us who had no dog in that fight lose.)

I pulled SO much of my hair out before I discovered the link between my iTunes issue and that Bluetooth driver. I ended up just removing BtTray as a startup item since it wasn't clear to me that it served any real purpose.  I'd be really curious to know the underlying cause here in order to figure out whether this is something that should rightfully be fixed by Widcomm or Apple, but for now my iTunes works as it should and so does Bluetooth, despite not having that BtTray startup item.

My view is that Dell is responsible for that piece of code getting on my system. They own this problem until they can find somebody else to push it off on.

Well ok, you can substitute Dell for Widcomm (although Dell would just have to lobby them to develop a fix anyway....), but until the technical cause of the conflict is known, my point was that it's entirely possible that Apple is doing something with iTunes that it shouldn't be.  But I don't have the tools or expertise to determine that, although even if I did, I'd be unlikely to commit the time given that my current workaround seems to have no negative consequences.