Some buttons not working with properly detected joystick

I have run all the examples that came with Qt5.8 with my Thrustmaster T.Flight Hotas X v.2 Joystick.

While most axis and buttons work great, there are a few that don't.

I have verified that the joystick is properly detected by the system with the following:

lennart@katana:~$ dmesg | grep -i "joy"
[16364.081697] hid-generic 0003:044F:B108.0006: input,hidraw5: USB HID v1.00 Joystick [Thrustmaster T.Flight Hotas X] on usb-0000:00:14.0-6/input0

I have downloaded and run jstest-gtk tool from official Ubuntu repositories to verify that the joystick in fact works on my system.

Using that tool, I have identified the buttons that don't work in Qt examples that work perfectly in the test jstest-gtk tool:

Button 0
Axis 4
Button 3
Button 4
Button 5
Button 6
Button 7
Button 3

I am not running any special software or tools that could interfere with this that I know of.