It's definitely frustrating to not have your microphone not working on calls and unable to use the text to speech feature. There could be a few factors may be causing this to occur, like an external device such as headphones, could be blocking the microphone or the type of case you have on the device.
First, Let's make sure your device is currently up-to-date to the latest software.
On your device, navigate to and open Settings.
Swipe to and then tap Software update, or System updates. It will vary between models.
Tap Download and install, or Check for software updates. If an update is available it will begin downloading, though you may need to tap Download now on some devices.
When the download is complete, follow the on-screen instructions to install the update.
Test the device in Safe Mode. This mode will disable all third-party apps from running in the background. If the microphone works in safe mode, then a third-party app could be causing this. I would recommend deleting your most recent apps until you are not experiencing the symptoms anymore.
open the Power menu:
On devices with a regular Power key, press and hold the Power key until the Power menu is displayed.
On devices without a dedicated power button, swipe down with two fingers from the top of the screen to open Quick settings. Tap the Power icon at the top of the screen.
Touch and hold Power off until the Safe mode icon is displayed. Tap Safe mode to start your device in Safe mode. If you've entered Safe mode successfully, you'll see Safe mode displayed at the bottom of the screen.
Now, if you are still experiencing microphone issues in Safe Mode, then I advise you to continue to try the other troublshooting below.
Next, factory resetting the device. I know this may not be the ideal step to take, but this will reset the device to its factory settings. Before you do this step, I recommend fully backing up the device to a cloud, to ensure you won't lose any data during this process.
Write down the username and password for the account that you used to back up your data.
We recommend having your phone or tablet plugged into the wall charger during the reset process because it may take up to an hour.
If you have encrypted the SD Card inserted in to your phone or tablet, make sure to decrypt it before the reset. Navigate to Settings, search for and select SD, and then tap Decrypt SD Card.
Navigate to Settings. Search for and select Factorydatareset. Tap Factory data reset again, and then tap Reset. Follow the on-screen prompts to complete the reset. You may need to enter your Samsung account password or Lock screen password. The phone or tablet will reboot.
After, the factory reset and the initial setup is complete and you are still experiencing microphone issues, a service repair is recommended.
