I recently experienced an issue where the microphone would not work intermittently on incoming or outgoing calls. I could hear them, but they could not hear me. So I started reading post on this, and many other, forums and blogs. I saw everything from a small piece of tape by the mic melting, to replacing the microphone procedures. Through my own troubleshooting, I could tap the Google speak microphone icon. After a few loud "hellos" into the mic, it would start working. This told me it was a software issue, although every post I read mentioned it being hardware. If it was hardware, it would be a consistent malfunction. I did not bother at this point to test with switching calls to speaker so I could focus on the software side. I am posting this to help others before taking the unit apart, buying a new one, or paying for repairs. If you experience calls where you can hear the person, but they cannot hear you, first determine if the issue is hardware or software caused. Do the obvious steps of making sure the microphone is not muted or the mic port is not blocked. 1. Once the issue occurs, hang up and on the main desktop screen, hit the microphone icon in the Google bar, or the mic icon on your on-screen keyboard. View attachment 70196 View attachment 70197 2. Speak into the microphone with one syllable words several times, increasing the volume of your voice each time, (I had to almost yell). Repeat until your voice is recognized. At this point, if the microphone picks up your voice, you have a software problem. Please proceed below. If not, reboot your phone and try again. if it still fails, check the microphone port for debris. (Tobacco flakes once kept my mic from picking up anything). Attempt the speaker mic test by simply switching to Speaker on the call screen and talk. If it works, I would still try the steps below, but you may have a failed microphone. 1. Clear the system partition cache. This will NOT delete any data or change your settings. https://motorola-global-portal.cust..._detail/a_id/93162/p/30,6720,8579/action/auth Test the microphone. (This did help clear the issue for about a day). 2. If the issue persist, check for any app or system updates. From the main menu, choose Settings>Apps. Make sure you are on the Downloaded apps page. 3. Tap on the first actual app. If there is any cached date, click Clear Cache. Click OK. View attachment 70198 4. Now click Force Stop. Most apps will also stoppage unless they are system critical. Click OK. View attachment 70199 5. Finally, click Uninstall updates. Click OK. View attachment 70200 Repeat for all downloaded apps. Reboot the phone once complete. Test the microphone. If not resolved, you may have to perform a factory reset, (hard reset), which will cause you to lose settings and data that is not backed up. If the microphone worked using the Google speak option, it is software and a factory reset will fix. Hard Reset - DROID RAZR HD / RAZR MAXX HD by MOTOROLA In my case, it was an app update that did not install correctly. I narrowed it down to Circles>Weather.com app. Phone has worked flawlessly since performing these steps. Performed all updates again and no problems. My friends were convinced it was hardware. BTW, I happen to work for one of the largest computer OEM's as a level 4 engineer and program manager, and every day I have to remind technicians that most all computer and phone problems are software caused, not hardware. But people just think hardware automatically these days. I guess I am old school after 25 years of computer work. Hopefully this will help someone with this issue before they do something drastic.