This issue occurs when you send or receive emoticon animations in Microsoft Lync 2013 (Skype for Business). When this issue occurs, emoticons keep animating, and that overuses CPU resources. This fix limits the number of times that emoticons can animate.
To resolve this issue, install the July 14, 2015 update (KB3054946) for Lync 2013 (Skype for Business).
Note Lync 2013 was upgraded to Skype for Business in April 2015.