These issues are the most common audio issues reported by users in the Apple support forum. There are some “Do it yourself” fixes available and advised to be attempted as a “first aid” for your audio issues by Apple professionals and users. Those are:

• Checking the ringer switch to see if it is on the sound mode
• Restarting Your Phone
• Disabling your Bluetooth in the iPhone 7
• Check if your phone is in DND (Do not disturb) mode
• Check sound notification settings and try turning noise cancellation off.
• Try using headphones and check if the sounds come okay in headphones.
• Try removing any protective cases
• Clean the speaker grills for dirt and debris

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