This thread solved my problem as well. I was using the generic USB drivers. I switched to ftdi_sio and it solved it!
Thanks!
Topic: [SOLVED] 5 BTC - Noisy ttyUSB0 line? (Read 1535 times)
Thank you! 
Seems like you are using the wrong kernel module for that device. Probably some generic usbserial thing instead of ftdi_sio.
The FTDI chip used in the BFL prepends two status bytes to the actual serial port data before transmitting them via USB, which result in that "2`" pattern. A correctly-working driver will interpret these bytes internally and filter them out from the data stream before passing it to the TTY.
The FTDI chip used in the BFL prepends two status bytes to the actual serial port data before transmitting them via USB, which result in that "2`" pattern. A correctly-working driver will interpret these bytes internally and filter them out from the data stream before passing it to the TTY.
SOLVED!
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