There are occasions when unexpected app faults cause your phone to cease generating sound. That said, it might be a one-off problem affecting popular apps like YouTube, Spotify, and others. Minor app issues may frequently be resolved by doing a soft reset or just restarting your iPhone. To begin, here's how to perform a soft reset on your iPhone 8 Plus:

1. On your iPhone 8 Plus, press and hold the Power button, which is now known as the Side button.
2. To totally turn off your iPhone, slide the Power off switch.
3. Allow your smartphone to turn off for a few seconds.
4. Press and hold the Power/Side button for around 30 seconds, or until the Apple logo displays.