If your Mac isn’t using the built-in microphone, check with the microphone manufacturer’s support site on how to troubleshooting your particular microphone.Try turning on the ambient noise reduction setting, if available (not available on recent macOS versions) Set the input volume to a level higher than the middle. Make sure the Internal Microphone is selected.
Regular dictation (not enhanced) is often blocked by your antivirus software when the data comes back into the program from Apple Servers over the internet.
Go to Apple menu > System Preferences > Language & Region and click the Plus (+) sign. Readers say that when they downloaded another language pack, it installed and reset their native language pack too. Follow steps from the bullet point about using the “Go to Folder” function in the Go finder menu.
Locate and delete the file: ~/Library/Preferences/.For many users, this was the fix that worked, either with or without Enhanced Dictation. On the left side, under the microphone icon, select Internal Microphone instead of Automatic or an external microphone. Go to System Preferences > Keyboard OR Dictation & Speech > Dictation.Enhanced dictation is not available in macOS Catalina+–instead, use Accessibility’s Voice Control Turn on Enhanced Dictation or toggle it off/on (or vice-versa).Tips for when your Mac’s dictation is not working
If you identify a specific app that’s creating issues with Dictation, check if there is an update for that app or contact the app developer for further investigation.This is time-consuming for sure but might provide valuable insight into what’s causing the problem If it works, test out each app one by one to see if there’s a particular app creating issues. Check if an individual app is causing problems.Manually change the microphone setting to the internal microphone or whatever microphone you use–do not select Automatic.Go Finder >Top Menu > Edit > Select Start Dictation, then press your dictation shortcut (default is Function Key (Fn) Twice.).Setting dictation off and on without restarting sometimes doesn’t fix the problem, but rebooting between off and on often solves the issue. If that doesn’t work, try turning off dictation and restarting your system.
Try turning dictation off then turning it back on.If there is a lot of noise, try to reduce it by shutting and covering windows, closing doors, using a headset microphone, or physically moving to a different space (if possible)