0xfe 0x3e when trying to upload Firmware via QGC V3.5.2

I want to upload V1.8.2 firmware using QGC. I can not do this by displaying a “Error: Sync: Send Command: Invalid sync response: 0xfe 0x3e” error when connecting Cube with a USB cable. Curiously, this cube was purchased recently. And another cube purchased about a year ago can be installed without any problems. Also, Audupilot’s firmware can be uploaded without problems with Missionplanner on this cube. Do I need any special instructions?

It should work without problems. Flashing is very tempermental to the quality of the USB cable as well as going through a hub. Connect directly to compute and try a different usb cable ifo things don’t work.

I do not think that this is a USB cable problem, I tested with a different cable or PC combination, but this CUBE alone does not work, and all my other CUBEs have worked.

try latest master QGC, I think the bootloader is changed from px4fmuv3 to cubeBlack

I have confirmed that it works fine with the master version of QGC.Thanks!