@Bordomboy
Are you using a powered hub?
do you have a ttyACM0 listed in your in /dev?
What command line are you starting bfgminer with?
At first I tried a hub, but couldn't find its power cord, so I plugged them directly into a USB expansion card installed on the machine.
Yes, I found ttyAMC0 and ttyAMC1 in my /dev.
I've been starting bfgminer with bfgminer -o stratum+tcp://us3.eclipsemc.com:3333 -u xxxxx -p xxxx -S bitfury:/dev/ttyACM0
I use -S bigpic:/dev/ttyACM0 - etc.