Hi Cowchaser,

Have you installed the latest S4 firmware from the bitmain site:

  https://bitmaintech.com/support.htm?pid=00720140930114518599JXGHWWD80660

and the latest S4-specific cgminer update from ckolivas:

  https://bitcointalk.org/index.php?topic=796839.msg9242133#msg9242133

Also remember that hashrates on Slush's pool seem to improve the longer you hash, so your hashrate may take 2 - 10 hours to reach the value its going to settle at.

thanks,

-dave