Is it possible to tell Windows not to lower the volume of the Skype for Business 2016 client when a call is detected?

Whenever I either receive an incoming call or make an outgoing call through the Skype for Business 2016 Windows desktop client, I’ve noticed that no matter whether I answer or reject the call, Windows lowers the volume of the Skype executable (lync.exe) from within the Volume Mixer – meaning that I manually need to go and turn it back up each time. Within the Sound applet of the Control Panel, I’ve set the setting in the "Communications" tab to "Do Nothing" so that in theory Windows won’t do anything when communication activity is detected – but this problem is still visible. I can’t find a setting from within the main Skype for Business GUI to disable this functionality – is what I’m asking possible to achieve?