There is no sound when connecting with Walkman or mobile device.

Perform the following procedure to solve the issue.

1. Check that the Headphone Amplifier is properly being charged.

2. Turn off and on the Headphone Amplifier.

   1. Turn the Power/volume knob to the left to turn off the Headphone Amplifier. Turn the knob until it clicks.
   2. Turn the Power/volume knob to the right to turn on the Headphone Amplifier. When the power is on, the CHG POWER lamp flashes in green, then lights up.
      
      

3. Check that the connection between the Headphone Amplifier and other devices and the settings of the INPUT switch are correct.
   
   

   • Select your device 
     
     For PHA-1,PHA-2
     For PHA-1A, PHA-2A, PHA-3
     Connection with Walkman
     Connection with iOS device
     
     
     
   • • For PHA-1, PHA-2
       1. Check whether the Headphone Amplifier connects with the stereo mini cable that comes with it.
          
          [A]: Cable that comes with the Headphone Amplifier.
       2. Check whether the INPUT switch settings match the AUDIO IN.
          
          [B]: AUDIO IN input switch
       3. If there are no issues, continue to Step 4.
          
          
     • For PHA-1A, PHA-2A, PHA-3
       
       
     • 1. Check whether the Headphone Amplifier is connected using the Xperia cable that comes with it.
          NOTE: Do not use the cable that comes with your smartphone.
          [A]: Cable that comes with the Headphone Amplifier. 
          
       2. Set the Headphone Amplifier's INPUT settings so that the connected port is in effect.　
          
          
          [B]: AUDIO INPUT switch.
          Confirm whether the INPUT switch settings match the AUDIO IN.
          
          IMPORTANT: When using Xperia Z4 or Xperia Z5, perform the USB settings.
          
          See below how to perform Xperia connection settings so that PHA-1A is recognized by Xperia.
          
       3. Turn on PHA-1A power before connecting to Xperia.
          1. From your Home screen on your Xperia device, tap .
          2. Find and tap Settings > Device connection > USB Connectivity > Detect USB device.
             NOTE: When you disconnect, you must perform the settings above when reconnecting.
             
             
       4. If there are no issues, continue to Step 4.
          
          

   • Connection with Walkman

     1. Connect the Headphone Amplifier to the Walkman using the Walkman cable that comes with the Headphone Amplifier .
        NOTE: Do not use the cable that comes with your Walkman.
        
        
        
        [A]: Cable that comes with PHA-2
        [B]: Cable that comes with PHA1A, PHA-2A, PHA-3
        [C]: Cable that comes with PHA-1
        
        
     2. Attach INPUT switch to the access point.
        
     3. If there are no issues, continue to Step 4
        
        
   • Connection with iOS device
     
     

     1. Connect iPhone/iPad/iPod to the iPhone/iPad/iPod port using the USB cable supplied with your device.

        

     2. Attach INPUT switch to the access point.

     3. If there are no issues, continue to Step 4.

4. Check that the headphones are fully connected to the headphone port. Check that they are not connected to the Line IN/OUT ports.

5. Check that sound can be heard from the headphones when you playback the connected device.