First, make sure you're in Auto mode in the app, as this is the part of the app that can listen to you (Manual mode will only play reference sounds for you to tune by ear).
Next, check the line of dots at the top of the screen. These should be lighting up according to the volume of sound the app is picking up.
If you don't see any incoming sound using the volume meter, the app may not have permission to use your device's microphone.
To fix microphone permissions on iOS devices
- Launch the Settings app on your iOS device, then scroll down until you see Fender Tune and tap on it.
- You should see the option to Allow Fender Tune to access with Microphone listed below with a toggle next to it. Make sure it's toggled to on (so it displays as green).
Now the app should be able to hear you tuning and give you appropriate feedback. If you're still having issues, try restarting the app or the device.
To fix microphone permissions on Android devices
- First, navigate to the Settings app, and select Apps or Applications
- Select Fender Tune
- Select Permissions from the App Info screen
- Enable the Microphone permissions