• Examine your sound preferences.-If your device has a Ring/Silent switch, shift it forward so that orange isn't visible. If you're using an iPad, you can also see Control Center and ensure sure Silent Mode is turned off by swiping down from the top-right corner. Make sure Do Not Disturb is turned off by going to Settings > Focus > Do Not Disturb.
• Make sure your speakers and receivers are in good working order.-Remove any screen protectors, films, or cases that may have been applied to your smartphone. Examine the speaker aperture for obstructions or dirt. Make sure the receiver on your iPhone isn't obstructed or filthy. If needed, use a small, soft-bristled brush to clean the speaker or receiver opening. Make sure the brush is dry and clean before using it.
• Make sure your device's sound is turned on.-Drag the Ringer and Alerts slider back and forth a few times in Settings > Sounds (or Settings > Sounds & Haptics). If you don't hear anything or the speaker button on the Ringer and Alerts slider is darkened, your speaker may need to be repaired. If you have an iPhone, iPad, or iPod touch, contact Apple Support.
• Make a phone call.-If you hear sound, try making a call on your iPhone with the speakerphone turned on. Make a FaceTime call from your iPad or iPod touch. If you still can't hear, or if you hear static or crackling, the problem could be with your network or reception. Call back at a later time or from a different place.

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