GMSK_DEMOD question, please help me :)

Hello everyone,
I am an intern this summer doing signal demodulation and decoding.
I am using GNU Radio software to demodulate the 9600 bps 12.5KHz wide
GMSK
modulated signal.

Here is my process:
I get the data from the antenna, sampled it at 2.048MHz,
Go through a low pass filter and decimate the sample rate to 76.8KHz.
Then go through GMSK demodulator with 8 samples per symbol. (I think
this maybe the problem…) In this way,the output baud rate is 76.8k/8
= 9.6k

I could not get any repeated signal from this demodulation process. I
wonder if you could point out what I did wrong?
Thanks so much for your time!!!
Really appreciated!

Cindy