Automation is causing skipping

Newbie to Cubase 7 Artist…

  1. ) I have 21 tracks so far on the song I am working on.
    When I use the Volume automation as well as adjusting Roomworks reverb levels during automation it is causing the system to skip and stutter for a fraction of a second a few times during playback.
    Any ideas on how to rectify??
  2. ) Also it seems that when I had previously used automation for panning a track from left to right… that input seems to be imbeded now in the track and I can’t get rid of it…even though I have erased that automation signal and tried to record a new automation.
    any ideas?
    Thanks, Eric