• If your iPhone speaker is muffled or you don't hear any sounds, go to Settings > Sounds and drag the Ringer and Alerts sliders in opposite directions. If the speaker button on your product is dimmed, it may need to be serviced. You can potentially solve the problem by increasing the volume on your device.
• Once you've ruled out the volume controls and ringer alerts as the source of your iPhone's problem, there are a few more things to look into to get your phone back up and running.
• A software issue could be to blame if your iPhone speakers stopped working in the middle of a streaming session or an app activity.
• Go to Settings > Sound and Haptics to adjust the volume on your iPhone. Under the Ringer and Alerts heading, drag the slider. Your sound settings should be maximised if the toggle is to the right.

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