I'm having trouble with an FTDI dual serial device. The similar single serial device works fine. Every time I connect the dual device, it immediately disconnects (based on dmesg output). [ 204.379613] usb 1-4: New USB device found, idVendor=0403, idProduct=6010, bcdDevice= 7.00 [ 204.379617] usb 1-4: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [ 204.379618] usb 1-4: Product: Digilent USB Device [ 204.379619] usb 1-4: Manufacturer: Digilent [ 204.379620] usb 1-4: SerialNumber: 210319B57D18 [ 204.381907] ftdi_sio 1-4:1.0: FTDI USB Serial Device converter detected [ 204.381920] usb 1-4: Detected FT2232H [ 204.382163] usb 1-4: FTDI USB Serial Device converter now attached to ttyUSB0 [ 204.383217] ftdi_sio 1-4:1.1: FTDI USB Serial Device converter detected [ 204.383229] usb 1-4: Detected FT2232H [ 204.383460] usb 1-4: FTDI USB Serial Device converter now attached to ttyUSB1 [ 204.391697] ftdi_sio ttyUSB1: FTDI USB Serial Device converter now disconnected from ttyUSB1 [ 204.391706] ftdi_sio 1-4:1.1: device disconnected [ 204.391804] ftdi_sio ttyUSB0: FTDI USB Serial Device converter now disconnected from ttyUSB0 [ 204.391812] ftdi_sio 1-4:1.0: device disconnected I've uninstall the brltty (braille TTY) option and this did not make a difference. I've also tried some different /etc/udev/rules.d setups with no improvements. I have this working fine on a stand-alone Linux machine. It seems to be a problem with Parallels Desktop Pro.
