Joystick parasite commands

[JoeCool]

Hello everybody and happy new year to you !!

Since I have finished my Box, I have a little problem with my installation. The problem is that I have some parasite commands. Sometime, a right or left command is send without touching anything and during playing too.
My config is:
-Raspberry Pi 3.
-Retropie (new new version uploaded).
-Quimat joystick with USB converter (here: https://www.amazon.fr/gp/product/B06XDJBT43/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1)
-No USB Hub.

I have done some tests:
-If I unplugged the joystick (5 pins), the problem still exists .
-If I unplugged the USB converter, the problem disappers.
-If I test the USB converter (full plugged with buttons and joystick) onto my PC, I see no parasite. All seems to be good. I tried Joytester and http://html5gamepad.com/. Same result: no parasite.
-I unplugged the USB converter and plug in an usb joystick (like that: https://www.amazon.fr/gp/product/B00VZ0D7XG/ref=oh_aui_detailpage_o07_s00?ie=UTF8&psc=1). No parasite at all in my Box.
-I tried with a powered USB Hub, same parasites.

I'm very lost with this problem. So if somebody have a good idea and something to try, I'm ready to do that.

Of course, I'm going to try a direct connection (GPIO) but before that, if there is an issue, I take it.

Thanks a lot.
Joe.

[JoeCool]

Hi, after many and many tests, I finally found the jstest binary (onto rasbpian) and saw the parasites: random commands.

It was probably the USB converter (Dragonfire) that is faulty. I will receive and test a new one as soon as possible and will tell you if the parasites would disapear.

For the moment, I used an USB converter found in a little joypad (Gamepad USB) and all is works fine.

See you.