IPHONE CLOCK ALARM - NO SOUND!

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The information below taken from the following resource may provide a solution for you: How to set and change alarms on your iPhone

If the alarm volume is too low or quiet

Do Not Disturb and the Ring/Silent switch don't affect the alarm sound. If you set your Ring/Silent switch to Silent or turn on Do Not Disturb, the alarm still sounds.

If you have an alarm that doesn't sound or is too quiet, or if your iPhone only vibrates, check the following:

• Set the volume on your iPhone. If your alarm volume is too low or too loud, press the volume up or volume down button to adjust it. You can also go to Settings > Sounds & Haptics and drag the slider under Ringtone and Alert Volume.
• If your alarm only vibrates, make sure that your alarm sound isn't set to None. Open the Clock app, tap the Alarm tab, then tap Edit. Tap the alarm, then tap Sound and choose a Sound.
• If you connect headphones to your iPhone, the alarm plays at a set volume through the built-in speakers on your iPhone as well as wired and wireless headphones.

Manually adjusting the time on your iPhone in Settings to change app behavior, like game timers, isn't recommended and can affect alarms.

We hope this helps!