If you have multiple audio devices, for example, a USB phone and a USB headset, only one will be the default Skype for Business audio device. To change which device is default, click the audio settings button in the bottom right of the Skype for Business window and select which device is to be the default.
If you have a phone and a headset it is likely you will want the headset as your primary device but to have the phone to ring on incoming calls as well.
To set this:
- Click the audio settings button.
- Click Audio Device Settings.
- Under Secondary ringer, select the USB phone.
You can change your ringtone for different call types. In the Skype for Business options select Ringtones and Sounds. For each of the different Calls to you can change the ringtone.