Well I figured this out myself so thought I'd share in case someone else has the same issue.

Go to RETROPIE and open RETROARCH.

Go to settings and redo whatever buttons you need to for INPUT 1.

Go back to the main menu, into configurations then SAVE current configuration.

Job done, all works fine on SNES now.

Translated by google
Thank you very much for the guidance, it is 0:15 am here (city of Cabo Frio RJ / Brazil), I am replying to you from an RPi4, tomorrow I will record a Retropie image on the sdcard to use on the RPi3 and try / study the guidelines ok?
I'll be back here to post the results. . .
Again, thank you very much for your attention.

Muito obrigado pela orientação, são 0:15 hs aqui (cidade de Cabo Frio RJ / brasil ), estou te respondendo de um RPi4, amanha gravarei uma imagem do Retropie no sdcard para usar no RPi3 e tentar / estudar as orientações ok?
Volto aqui para postar os resultados . . .
Novamente, muito obrigado pela atenção.

I can see the font files from my Mac via FTP, and a number of 16x32 fonts seem to be the largest there is. That's fine, I hopefully I can just SSH in for 99% of things.

solved, there was no memory in my sd, and filezilla passed the games of a 1kb, that was the reason why they did not work

friend there were no positive results. still don't recognize it. Would there be more tests that you could recommend?

thanks that worked fine :)

Not nearly enough information to go on...

However, you probably want to make sure you don't have the file scanning turned off in EmulationStation.

thank you again.

@mitu said in master system:

I suggest you start with a fresh image and add your ROMs/BIOS files, leaving the configurations alone for this first step.

very well, that's what I'm going to do.
thank you again for your help and your patient to answer me. thank you and good luck

That did it! There was a wiring problem with the hotkey. I just unplugged it, configured select as the hotkey for both controllers and now it is running perfectly. Thanks :)

Ah, thank you very much! I don't know how I missed that option scrolling through settings.

I'm just waiting for gamers to visit and play this cabinet as 2p.

Thanks, looks like it was a dodgy set of speakers. I set the sound as per, robbed the speakers from my PC and now I have sound. Still seems quite low though.

@BuZz Right you are! I tried that one first but it still said no signal. Seems the HDMI cord I got with my Canakit is a bit touchy... Thanks!

@mitu that's worked - much better as es was sluggish before. Cheers

@cyperghost thanks for the confirmation, I guess I'll have to screw around with it some more.

@mitu edit. I had a / rather than a comma. No error..

That it working now 👍

I was planning on doing the same converting them to