Unable to flash MKS Robin Nano V3 (STM32F407) with KIAUH v5.1.3 due to DFU signature warning treated as error

[drackp2m]

Linux Distribution

Debian GNU/Linux 11 (bullseye)
KIAUH v5.1.3
dfu-util 0.9

What happened

After a recent update, I can no longer flash my MKS Robin Nano V3 board (STM32F407) using the "Regular" flash method in KIAUH. The process fails with the error message "No DFU capable USB device available" and exits prematurely.

The flashing process gets to the point where it shows:

dfu-util: Invalid DFU suffix signature dfu-util: A valid DFU suffix will be required in a future dfu-util release!!! dfu-util: No DFU capable USB device available

The error appears immediately after attempting to flash without giving the device a chance to enter DFU mode. Previously this process worked correctly, but now it fails consistently.

What did you expect to happen

The flashing process should continue despite the "Invalid DFU suffix signature" warning message, as it did before. The MCU should be put into DFU mode automatically by the script, and the flash should complete successfully.

In previous successful flashes, although the same warning appeared, the process would continue and successfully flash the firmware, showing messages like:

Opening DFU capable USB device...
ID 0483:df11
Run-time device DFU version 011a
Claiming USB DFU Interface...
Setting Alternate Setting #0 ...
Determining device status: state = dfuERROR, status = 10
dfuERROR, clearing status
Determining device status: state = dfuIDLE, status = 0
dfuIDLE, continuing
DFU mode device DFU version 011a
Device returned transfer size 2048
DfuSe interface name: "Internal Flash"
Downloading to address = 0x0800c000, size = 32284
Download	[=========================] 100%        32284 bytes
Download done.
File downloaded successfully

How to reproduce

1. Connect MKS Robin Nano V3 (STM32F407) board via USB
2. Run KIAUH and navigate to Advanced → Build and flash
3. Select the MCU (usb-Klipper_stm32f407xx_410029000A50325436303720-if00)
4. Choose "Regular" flash method
5. Select the firmware config file (in my case "super-racer.config")
6. Confirm flash parameters
7. Observe that the process fails with the error:
   "Failed to flash to /dev/serial/by-id/usb-Klipper_stm32f407xx_410029000A50325436303720-if00: Error running dfu-util"
   "No DFU capable USB device available"

My MCU configuration:

• STM32F407
• 48KiB bootloader
• 8 MHz crystal
• USB (on PA11/PA12)

Additional information

The key difference appears to be that now KIAUH treats the "Invalid DFU suffix signature" warning as a fatal error, while previously it recognized this as a non-critical warning and continued the flashing process.

I didn't need to press any buttons on the board for flashing before - the process was entirely automatic. This suggests that the automatic bootloader entry sequence is no longer working properly in the current version.

P.S.: This is issue has created with Cloud Sonet 3.7 thought Copilot Pro.