Unable to flash bootloader

[ssnake]

I feel like my px4 is bricked. Dfu can't see my device, but dmesg see:

[64435.467919] usb 1-1: new full-speed USB device number 38 using xhci_hcd
[64435.616742] usb 1-1: New USB device found, idVendor=26ac, idProduct=0011
[64435.616746] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[64435.616748] usb 1-1: Product: PX4 BL FMU v3.x
[64435.616749] usb 1-1: Manufacturer: 3D Robotics
[64435.616751] usb 1-1: SerialNumber: 0
[64435.617376] cdc_acm 1-1:1.0: ttyACM0: USB ACM device
[64440.171525] usb 1-1: USB disconnect, device number 38
[64441.607822] usb 1-1: new full-speed USB device number 39 using xhci_hcd
[64441.756909] usb 1-1: New USB device found, idVendor=26ac, idProduct=0011
[64441.756914] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[64441.756917] usb 1-1: Product: PX4 FMU v2.x
[64441.756920] usb 1-1: Manufacturer: 3D Robotics
[64441.756922] usb 1-1: SerialNumber: 0
[64441.757674] cdc_acm 1-1:1.0: ttyACM0: USB ACM device

$ dfu-util -l
dfu-util 0.9

Copyright 2005-2009 Weston Schmidt, Harald Welte and OpenMoko Inc.
Copyright 2010-2016 Tormod Volden and Stefan Schmidt
This program is Free Software and has ABSOLUTELY NO WARRANTY
Please report bugs to http://sourceforge.net/p/dfu-util/tickets/

However, I can flash firmware via QGC. It flashes, but after reboot PX4 doesn't accept any command fro QGC

[LorenzMeier]

Sorry for not noticing this earlier - closing now as stale.