Serial port framing error
Your actual baud rate with those settings is 38400. If TXSTAbits.BRGH == 1, then the multiplier is 16, not 64. If you want 9600, then either set TXSTAbits.BRGH = 0 or SPBRG = 129 (20MHz / (16 * 9600))-1.

See the EUSART chapter of the datasheet for more details.