When you are on one of those extended lunch breaks it can be really annoying that Lync reports the time you have been away.
This can be disable on a per Lync Front-End Server basis as follows:
Create a new text file on the Lync front-end server in the following directory.
Lync 2010 %Installation Folder%\Microsoft Lync Server 2010\Server\Core\
Lync 2013 %Installation Folder%\Microsoft Lync Server 2013\Server\Core\
The name of the text file has to be : Rtcaggregate.exe.config include the following configuration entry :
After the text file is saved restart the Front-End Server service (RtcSrv) to apply the changes.