Depending on wich baudrate you perform it too. Is it doing the same garbage stuff on 2400 bauds? If you're using PIC to Send data to the PIC may try to add

DEFINE CHAR_PACING 1000

and post what happen. If you're using Hyperter, Microcode studio, be sure of the polarity of your SERIN ... i.e True/inverted.

Case you use Hyperterm you must set SERIN inverted if you're not using any RS-232 inverter (Like MAX232) .

example for 2400 BAUD

SERIN Serpin,4,SerData 'receive data from PC inverted

with this, be sure of your resistor between PIC and PC. Work good between 1K and 10K.