31When external speakers are not connected or only thebuilt-in speaker is enabled, press the volume + and -buttons ( ) to adjust the volume.If external speakers are enabled, perform the followingprocedure to suit the environment they are used in.■When both the built-in speaker andexternal speakers are enabled:1. Set the volume of external speakers to the minimum.2. Press the volume + and - buttons ( ) to adjust thevolume of the built-in speaker.3. Adjust the volume of external speakers.■When only external speakers areenabled:First, take steps 1 to 3 described below to fix the volumeof the external speakers. Then, use the volume + and -buttons ( ) of the product to adjust the volumewhen you are using the product.1. Set the volume of external speakers to the minimum.2. Press the volume + button ( ) to set the volume tothe maximum.3. Adjust the volume of the external speakers to themaximum level available during use.4. Press the volume + and - ( ) buttons to adjust thevolume to the desired level.When adjusting the speaker volume, be careful to causeno sound cracking. Sound cracking may cause an echophenomenon on the other side.yIf you operate the volume + and - buttons ( ) of theControl Unit, you can adjust the volume of both the built-inspeaker and external speakers.If a PC or a Mac is connected using the USB cable, its speakervolume is adjusted synchronously.Temporarily stop the microphone so that the other partydoes not hear a voice in this side.■Muting the microphonePress the microphone mute button ( ).The microphone status indicator lights up red, andmicrophone muting starts.■Canceling microphone mutingPress the microphone mute button ( ) duringmicrophone muting.The microphone status indicator lights up green, andmicrophone muting is canceled.yThe microphone muting function is synchronized with allmicrophones. If one microphone is muted while multiplemicrophones are connected, all of them are muted.Even if this function is enabled, external microphones willnot be muted.Temporarily mute the speaker so that incoming soundscannot be heard.This function is available only when a PC or a Mac isconnected using the USB cable.■Muting the speakerMute the speaker on a PC or Mac.The volume + and - buttons ( ) flash green, and thespeaker is muted.■Unmuting the speakerUnmute the speaker on a PC or Mac that has beenmuted.The volume + and - buttons ( ) light up green, andthe speaker is unmuted.yThe speaker can also be unmuted by pressing thevolume + and - buttons ( ).Adjusting the speaker volumeNoteMuting the microphoneNoteMuting the speaker