Samsung Galaxy Z Fold5 microphone is quiet, muffled or not working

The checks in more detail

Test with the Voice Recorder, a video and a call at the ear, and with the phone open and folded. Remove the case and brush the openings. Turn off Bluetooth in case the call has moved to a headset, and check noise reduction in the call settings. App permissions under Settings, Apps, Permissions matter for a single app. The Samsung Members microphone diagnostic tests the hardware. A crease protector or case edge can cover the top microphone. Restart and wipe the cache partition after an update. A recording silent in every state needs a repair.

Because the cover screen and the inner screen use different top microphones for some modes, a call made on the cover screen and then moved to the inner screen can change the microphone used, which explains a voice that changes in quality mid-call. Keep one posture and test each. If you use the Fold5 for meetings with the phone propped in Flex mode, a laptop-style stand puts the microphones at a distance from you, and a headset or the phone's speakerphone with the phone close to you gives a better voice.

In noisy places the noise cancellation can cut the voice, and turning on Voice focus in Samsung's call settings makes it clearer. Samsung's foldables include a feature that changes how the screen is used during calls; the call controls on the cover screen and the inner screen differ, and you may be speaking toward a microphone that is not the active one. Try the call on speaker with the phone flat in front of you, then at the ear, and note which sounds clearer to the person on the other end.