Help help. GPIO is strange

[JoeCool]

Hello,

I posted here this message because I have no solution. I searched all possibilities (I'm going to give details below), tried thousand of things but for now, my GPIO doesn't work.

I'm really hopeless.

My Project is to do a retrogaming box with Raspberry and Retropie.

Here is my configuration:
Raspberry 3
SD: 32 Go
Distribution: Retropie
Real Joystick and buttons: 4 switches for the Joystick and 8 switches for the 8 buttons (A, B, X, Y, Start, Select, Shoulder L and Shoulder R).

First, I try to connect my Joystick and buttons into an USB convertor (Dragonfire). All works fine but sometime, I have parasites and bad commands (5 per minutes). I considered, this was not acceptable.
I decided to test another USB convertor and take those of my USB SNES Joystick. Fantastic, no more parasite.
Unfortunately, 2 weeks after this big victory, parasites returned. I don't know why.

I tested joystick whit jstest and saw theses parasites. While I did not touch anything, I saw commands into jstest.

I supposed it was a problem with my 2 USB convertor (bad quality) and decided to connect buuton and joystick directly on the GPIO.

Here, the first difficulty I it was: how obtain joystick and buttons into emulationstation or more simply, how to obtain jostick under jstest.
I tested mkarcade, Adafruit, retrogame, nothing at all, but no one of these possibility gave me a functional joystick.

Adafruit and retrogame (seems to be the same) give me no joystick under /dev/input.
mkarcade gives me a joystick under /dev/input but the parasites are here.

A word about this parasites: I launch jstest and see my event when I push a button or joystick but sometimes, I see parasite events and my emulatiostation graphical evironment changes.

A precision: If I deplugged all my wires, I have no event under jstest but if I plug just two wires (connected to a single button, GND and GPIO04 for instance)
I obtain an event when I push the button but the same event seems to arrive without touching anything. About one per 10 sec.
If I just plug two wires with no button or switch, I obtain these parasites. Strange, no ?

Unfortunately, after wiring, the parasites was already here.

So my question are:
-what library should I use to obtain joystick under jstest but with no parasite ?
-what package should I install for that ?
-what package should I desinstall for that ?

I saw different packages under retropie_setup.sh (Manage Package/driver). For instance: controlblock, gamecondriver, mkarcadejostick, snesdev etc... Which one are useful or not.
My idea (today) was to desinstall all these packages and try to obtain jostick under jstest but not easy to know the truth in this bazaar ^^ !

Finally, I tried to search a response with pull-up, tried to pull-up up, down and off these resistors, but nothing better.
I used pigpiod with the pigs utility (pigs pud <n> >u/d or o>).

I think I gave you all I have done and sorry for my english, I'm french.

Please, help me to see more clearly and help me to go out this dead end.
Joe.