How to reduce the volume of the intercom extension of Huaying Building

In the external test of the extension, there is a rotary switch to adjust the sound.

Building intercom, indoor extension is very loud. You can lower your voice appropriately. If the maneuver cannot be adjusted. With your hands. Generally, there are wheels on the side of the intercom extension in buildings (the last two are limited to visual intercom extensions) to adjust the volume, ringtone music switching, contrast and brightness. If the volume is turned to the minimum, it will only be replaced. Contact the property. Generally, as long as it is not a brand-name equipment, it is available after sale.