MCP 23s17 testing set-up problem/question

Hello I am experimenting with the MCP 23S17  expander, and have fabricated a circuit  with a PIC 16F1516 mounted on one bread board with  the serial connection made by  a 8-line CAT5 cable to the 23s17 mounted on a second breadboard with LED's connected to  the  PORTA and PORTB pins  as outputs.(I have no  resisters in line with the LEDs)  The  8 line cable  supplies the cs, sck, and dat pins as well as  a common ground and 5.1v vdd.  The  circuit  operates  as expected for a short  while then it seems to freeze.  I am just sending a series of   byte values to step through the LEDs.  When the freeze   occurs all I have to do to  unfreeze it is touch the  MCP23s17 with my finger or sometimes  just passing  my hand near it will do the trick. Is there some   capacitance  problem I am having with my circuit? Any suggestions would be appreciated.    John C