https://forum.recalbox.com/topic/8314/unable-to-update-to-unstable-version/9

you need to get the dtbo file, take a look a the page https://github.com/recalbox/recalbox-os/wiki/Utility---Use-of-fbcp-for-small-TFT-screen-%28EN%29 and https://github.com/recalbox/recalbox-os/wiki/TFT-Screen-SPI-Bus-(EN) if you do not use the 4.1 release

Meant to add, I just make an image of the card before doing any upgrades then if it goes belly up I'm back in business with a few mouse clicks.
As for why need a card so big - I've still ran out of space! Got 152 PSX eboots plus loads of PSP and Dreamcast images.

@kimmykaroo
I thought it was just me that found that video incredibly loud!

Understood. Thank you.

there didn't have a retroarch bug in current unstable release about gamepad assignment,
fixed on dev release ?

@dragu well, open a bug at libretro if you believe the rewind option is buggy, but you'll need some strong techbical arguments 😉

Very well guys,

I was able to solve my problem.
I feel happy because I do not have great knowledge of this area, only determination.
After finding the problem, quoted in the post above, I solved the problem by putting a command at boot:

Echo "power on" | Bluetoothctl

Every time you start the machine bluetooth devices start normally.
Sorry for my bad English and sorry for the posts in a row.

Problem solved.

Links that helped me:
https://wiki.archlinux.org/index.php/bluetooth
https://forum.recalbox.com/topic/3206/bt-controller-does-not-autoconnect
https://github.com/recalbox/recalbox-os/wiki/Add-your-own-startup-script-(EN)
https://raspberrypi.stackexchange.com/questions/44520/bluetooth-autoconnect-on-reboot-car-setup-with-scripts

Nevermind. Worked fine, thank you very much!!

@dragu the 4.1 stable will have an improvedaudio device selection (depsite the one now works, but not amways good)

@anonpebbles yeah, acris made a post for pi0w. It will be supported with 4.1 stable release

@rockaddicted

That sounds great thank you!!

@Dragu you can see the needed conector here:
https://github.com/recalbox/recalbox-os/wiki/Connect-your-recalbox-to-a-CRT-with-composite-(EN)

@danimourinho bad quality psu don't deliver what they promise. Sometimes the adapter itself is good, but the micro USB isn't.

@Homer @Substring

It really pitiful to see that Brazilians like to profit from other people's things.

You can get the unstable for all platforms here:

https://archive.recalbox.com/updates/v1.0/unstable/

If that answers you question.

I installed a heatsink, but one of the larger 20x20x20mm ones.
No problems since then, I don't think a fan is required.