NO question about it this is a major issue. I have an iPhone6 and am upgraded all the way to iOS 9.1. Voice Control has demon-possessed my iPhone, in fact that as I'm writing this post, it keeps going on and off, won't let me access my apps, even to look up Settings and try to fix. It happens both WITH and WITHOUT headhpones and regardless whether music is playing or not.
Seems it may be a hardware issue as it begain happening after I had some issues with a portable music player jack (and then headphones) but frankly I don't think they are related. Seems hardware related for sure. Also, now my phone has trouble, answering, listening, hearing interruptions - a SOUND cluster f... Complete disaster.
Wish I had a solution, but here's mine: going to get a new iPhone. Fortunately I purchased insurance, but this should be a warranty thing and non-issue. My phone is only a few months old!
Apple needs to fix this and do a "recall" so everyone who has a legit issue can get new phones.