Problem

After a call is put on hold, the call may drop after 10 seconds in certain instances. This does not happen always. Dropping calls could happen due to missing audio towards the caller/callee. When audio is missing certain networks send a BYE towards the trunk after x amount of time (mostly 10 seconds). The reason for dropping the call are Cellular phones working on VOLTE 4g calling. A timer runs when no audio is received, when no audio is received for 10 seconds the call will drop.

How to check

1. Call user personal direct phone number.
2. Put the call on hold.
3. Caller should hear Music on Hold or beeps to indicate that the call is on hold.

Solution

Add client music on hold when holding a call.

1. Enable client music on hold in the client policy.
   1. Go to the Skype for Business portal (https://portal.thevoiceofo365.com)
      
      
   2. Open the menu tab Policies and select Client policies
      
      
   3. Edit the policy assigned to the affected user
      
      
   4. Make sure the checkbox Client music on hold is checked
      
      
2. Configure the Music on Hold on the client.
   1. Open the Skype for Business client
      
      
   2. Click on Settings
      
      
   3. Open the tab Ringtones and Sounds
      
      
   4. Select Browse under the Music on Hold option.
      
   5. Select an WMA file you would like to use as Music on Hold.
      File to be used (example): zen_converted.wma
      
      

      Files on network drives

      IMPORTANT: Make sure that he file is reachable from the Skype for Business client. When Skype for Business is used on network drives, please make sure the client can reach the default Music on Hold file. Or add a new music on hold file that the client is always able to reach.