Yes, it's true. The iPhone's built-in speakers emit sound, whether it is lowering the volume at the volume button or control center, connecting wired / wireless headphones, or placing the side switch in an orange visible position (mute mode). You need to pay attention to places where you can't make a sound, and where you don't make a sound carefully, you need to pay attention to it.
Regardless of the state of the sound setting, the alarm / timer sound and the camera shutter sound will sound from the built-in speakers. Even if you have wired / wireless headphones connected, the built-in speakers will make sound, regardless of this. The alarm / timer sound can be volume adjusted, but cannot be completely muted (muted).
When in mute mode, the ringtone or notification sound is not heard from the built-in speakers. Most applications, such as games, also disable built-in speakers and do not emit screenshots and other operating sounds. With the exception of applications for music / video playback (which can be played / stopped using the operator panel in the upper right corner of the Control Center), the built-in speakers emit sound even if they are in mute mode.
However, if the iPhone does not sound well, make sure the switch on the side is in orange mute mode, make sure that the alarm clock / timer is not set, do not take photos, and do not start the music / video playback application.
This is almost foolproof, but it is also possible to receive emergency KuaiBao notifying the earthquake, tsunami and other dangers. After receiving the emergency KuaiBao, no matter whether it is in mute mode or not, the warning tone will be issued at the maximum volume, so if you want to be silent anyway, please consider turning off the "Emergency KuaiBao" switch on the "setting" notice screen.
