Set
OSCTUNE = %00000000

And try this
Code:
DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 20h ' Enable transmit, BRGH = 0
DEFINE HSER_CLROERR 1 ' Clear overflow automatically
DEFINE HSER_SPBRG 51  ' 9600 Baud @ 8MHz, 0.16%
SPBRGH = 0
BAUDCON.3 = 1         ' Enable 16 bit baudrate generator