This service package fixes the issues that are described in the following Microsoft Knowledge Base (KB) articles:
- 2919506 Can't hear the first few words that a callee speaks when they answer a call in Lync 2013
- 2919507 The "Program Events" sound setting is reset to the default value after you restart Lync 2013
- 2919508 Can't rotate the screen orientation of a video window in a Lync 2013 video conference on a Windows 8.1-based device
- 2919510 A pie chart clock icon appears in the "Conversations" tab as a meeting icon in Lync 2013
Edit:
A few additional changes have been announced that were included in the SP1 office upgrade
- Toggle pictures of sender/receiver
- Support of high-resolution monitors (200% scaling mode) this change makes Lync scale properly when you adjust the DPI on your monitor to 200%.
- Transfer files and pictures in a Persistent Chat room