I am having the same problem. voice prompts stopped working when I updated to 3.12.118. I tried rebooting, restarting the system, repairing the installation etc. When I disable and enable the voice prompts I hear the 'voice prompts activated message, but no prompt to tell me if the mic is active or not. My firmware is .15 and it says I have the latest one. I also tried forcing the firmware update. Not sure what to try next. I have windows 10 and and Alienware laptop.