I have a similar if not identical issue with my Z10, STL100-3 as well. I was on OS 10.2 (can't recall which one) and today updated to 10.3.1.2267 and the problem remains. This seems not to be an OS issue as it started "all of a sudden" about 2 weeks ago. If I plug my headset in, it works fine so I assume the problem is with the mic. I've ordered a new mic which I'm yet to receive. I'll see if that solves it.
02-12-15 05:36 PM