[SOLVED] Strange ghost inputs using Dual shock 4

[BobHarris]

So for the last few months I've been trying to figure out which controller to use for my Pi 3B. I wanted one that has a joystick (so I could play 3d platformers) but also has a great dpad for fighters. And it had to be reliable.
So the dual shock 4 v2 ticked all those boxes.

I grabbed one during my holiday in Japan. After I got home I tried it out (wired) and man I was satisfied. The size of the gamepad is just perfect and all the buttons and the sticks feel very sturdy. In Street Fighter I have no problems doing as many shoryukens in a row as I want.

But I have noticed one very odd issue. When I enter the rom list of my Playstation games, at seemingly random moments right after I press up or down (or l1, r1), the system keeps scrolling on its own. I can continue this in other rom lists if I press left or right during this scrolling. This also happens if I go out of the rom list into the emulation station home menu. In this home menu I can stop it by pressing up or down. Then it won't reoccur unless I start scrolling the Playstation games again.
I can't replicate this behavior in any of the other rom lists I got..it only starts in the Playstation rom list.
I've made a video of the issue:

I still prefer the dual shock 4 over any of the other controllers I've considered and tried out, but I would be very happy to hear about a solution. Sometimes it's a real pain to choose a game if I keep scrolling past it. At least I don't notice any ghost inputs in games (so far).
I already deleted all controller configurations, but that didn't have any effect. Also I use the controller wired, so it can't be a bluetooth issue.
By the way, the problem is gone if I assign the dpad buttons to the left stick. (But then I can't use the dpad anymore.)

I'm on Retropie 4.2.

[pjft]

How did you set up the controls in ES? Meaning, are you using the dpad to navigate, or the left stick? In my case, I notice that my DS3 left stick doesn't have a big deadzone, so in games with analog input it's very rarely stopped in the center.

Can you trace the behavior to any particular game in the list, our of curiosity?

[BobHarris]

@pjft Like I said: When I set up the controls in ES using the dpad for navigation, the issue occurs. When I assign the left stick instead, it works fine. Even then I can still make it happen by using l1 and r1 for scrolling.
It doesn't seem to be caused by a single game, it can happen pretty much anywhere in the list and it can also not happen while scrolling through the same games.

[BobHarris]

I kind of solved it. The only thing in which the ps1 folder differed from the other folders was the games' box art: Some of them were personal instead of scraped. I deleted all the box art and now there is no automatic scrolling issue.

I noticed before I had this issue that sometimes ES would hang for a second while scrolling. Something related to the boxart (maybe image size?). I now noticed the automatic scrolling in the snes folder as well, right after the system lagged a little bit.

Update: Reducing the size of all boxart jpeg images to <100 kb eliminated the issue completely.

[pjft]

@bobharris I am puzzled as to why that is happening, but glad you're sorted.

I wonder: do you have any particular power savings settings enabled on ES? What are they set for?

Thanks.

[BobHarris]

@pjft
My power settings are the stock settings.
I think this is what happens: When the boxart image size is large, the Pi needs a bit of time to load the image. This causes a slight delay when scrolling from one game to the next. Other controllers ignore this, but the DS4 seems to remember the directional button input during the delay and keeps it going, without me having to press the button anymore.
But yes I am very glad I found the solution. Thanks for your input, as you asking me if specific games were causing this, got me on the right track.