The thread being set as "Need More Info" is wrong, and I saw the same "response" on threads with the same issue.
I provided all the info needed, so what more do you need?
It seems to me that this problem still exists for a lot of people and most of them tried all the possible solutions, which none of them worked.
Is there something that I didn't try that I could do?
Also, sorry if I didn't answer correctly your question, but no, no other programs that may use the microphone are open together with DayZ, only Steam (that I tried with Friends open and closed).
All my apps and games when using the microphone, it shows the icon on the tray, but this is not true for DayZ and DayZ only.

In T156420#2154685, @juanmaevil wrote:

I am with the same problem since 1.09 this happened after I lowered all the volume of the sound of the microphone (since there was a guy yelling through the speakers) in the game menu, after that I could never speak into the microphone again

Hi Geez,