If you search the forums for that property, this post pops up:
http://community.wowza.com/t/webrtc-playback-pulsing-issue/50539
We do not have a way at the moment within the application.xml to edit that property. But, the post I shared offers a way to do that with a little of custom code. We do have a bug request in for this property to be edited so I apologize for any inconvenience.