Apple issued the iOS 11.0.2 update in October that fixed cracking sounds in the iPhone 8 duo, but now the iPhone X has seemingly developed a similar issue. Users reported a cracking and buzzing sound through the earpiece speaker at high volumes that appears in calls, during video playback or when listening to music. One user says a little cracking is heard whenever the volume is at max levels. It was noticed on certain songs and even with a ringtone, bought through the Apple Store. The sounds may be the result of distortion since they are heard only at higher volumes. Because of...
Source: https://www.gsmarena.com/iphone_x_earphone_bug-news-28222.php