I built the kit, I created a boot SD, and the device does not boot. When I switch it on with a newly created 64 GB SD card, the red LED on the raspi 5 goes on briefly, and then the green LED goes on and stays permanently lit. As a test, II booted the SD card in another raspi5. There, the raspi5 briefly lights up the red LED and then the green LED blinks. Thent I get a regular boot sequence, and then the screen with the female face. After that there is an error message about MIDI (and audio?) setup.So the SD card seems to be ok.
I then rewrote the SD card again (to have a clean image) and tried again. Same problem.
I get es far as the red LED briefly light up and then the green LED permamently staying on, no blinking.
Is there a way of debugging so i can locate the problem?
It sounds like something is a bit wrong with the connection from the RPi uSD socket to the Zynthian mainboard. I recommend you check the flat cable connection carefully. You could also try plugging the sdcard directly into the RPi temporarily to see if that works.
I would not rule out the possibility that it is a bad-incompatible sdcard - was the other RPi that you tried also a pi5? The Pi5 has a much faster signal rate to the uSD card, so it is much more sensitive to problems with the card. If you have another 32 or 64 GB SD card that would be worth a try.
Putting the SD card in the slot on the raspi makes things work. The connector cable from the main board to the SD card slot on the raspi might be the problem. Can I get a replacement?
Since this is small you could just put it in an envelope.
My original order # is SO13392.
If that cable is bad Iām sure @jofemodo at Zynthian Labs will send you a replacement. But at this point I think thatās still rather unlikely. Have you checked the connections at each end?
And do you have another good branded 32 or 64 GB sd card to try? The cable, even a good one, introduces some additional load and delay so if the card is marginal that could still be the problem. What brand and model is the card?
I am not a Zynthian Labs employee, just a fellow Zynthianer trying to help.
The card I use is a 64 GB SanDisk Extreme.
I also tried a 128GB Transcend 400x.
Iāve had issues with cards bigger than 32G in the past.
Yeah, thereās definitely an issue with bigger SD cards, Iām not sure how much of that is due to some intrinsic incompatibility with Zynthian-RPi, I think itās mostly due to the bigger the card, the greater the odds that itās counterfeit!
Iāve had the best experience with Samsung and Sandisk 32GB cards.
Also, the program you use to write the card can make a difference - the two Iām familiar with are Balena Etcher and Raspberry Pi Imager. At various times one or the other seems better, despite doing a verify after the write.
Iām sorry that this all sounds so Voodooish, but I would suggest trying a 32GB Samsung or Sandisk and both writer programs to see if you can get a happy card.
Or you can request a replacement cable, but I personally find opening up the Zynthian and replacing the cable more work and less successful than getting the ārightā SD card and writer program.
In the long term, Iām hoping this issue goes away with NVMe drives!
Counterfeit cards are certainly a prolific problem but even with genuine devices, my experience has been poor with larger capacity - not just on zynthian. I worked on a project deploying Windows 10 using Integral 128GB USB sticks and they were pretty unreliable. I have an Integral drive in my pocket today and have low level of trust in it (even though this one hasnāt given me reason to be concernedā¦ yet!)
I just read this in another topic, so if you want to go that route you should have a spare cable already. But I would still suggest trying a 32GB card first as the easier and more likely to lead to success.
Iāve used Raspberry Pi Imager and canāt honestly say Iāve had a problem with any 32G that arenāt beyond saving and are recognised when they mount. Mine are generally Sandisk Ultra 32G with occasional āothersā along the way. I tend to keep five or six of them and cycle throu them as I burn new SSDāsā¦
Hi, unfortunately Iām having the same issue. Built my 5.1 kit, flashed the disk image using Etcher to a Sandisk 32GB, and itās just a solid green light whether I plug the SD into the extender or directly into the socket. Itās the lite 9GB stable image. Solid green light and a dead screen.
Used Etcher (in admin mode) so far, on windows laptop. Might try Raspberry Pi imager next. And might try my Mac laptop too. Also, another card coming Monday.
Failing those two things, are there any other Zynthian users in the UK who could troubleshoot it for me? I donāt currently have the time in life (or the skills) to troubleshoot these things. Thanks.
I had problems of getting functional oram burned both with etcher and raspi-imager with couple of sd cards in my linux mint. The built in disk back-up tool however was successful in both of those. Worth a shot if you have linux systems available.
I only have Windows and Mac laptops. Only tried win so far, may try Mac when the new card arrives.
Thanks btw!
For several versions now Balena Etcher has not worked for me, Raspberry Pi Imager does work.
Itās booting from the SD in the Pi, but the first SD card extended doesnāt work. Iāll try the 2nd now. At least it boots!
2nd sd extender no good either 
And now Iām just getting an error on boot, sad face, even with the SD card directly in the slotā¦letās hope the new SD works.
Hi @paulee! I may be stating the obvious, or repeating something already written here, but from my standpoint the safest troubleshooting bet, for excluding altogether worst scenarios, would be:
- burning a SanDisk Extreme/Ultra 32/64 Gb with Raspberry Imager on Mac, and sliding the card directly in the Raspberry SD holder. This operational context never gave me a single issue across the years with my Zynthians.
Having booted successfully in this way, you might look at potential other problems, like a faulty SD extender harness, big size cards (I never use 128 GB) or ineffective OS+etching app combinations.
Best regards 
I have 2 pcs Scandisc cards with 128GB.
Started with one September 2024, burned with Raspberry Pi Imager on Windows 10. Never had issues. Burned the second one 2 days ago as a backup. Both work properly.
Thank you @zast , that is interesting and good to know. Is the manufacturer actually āScandiscā (I couldnāt find em with a quick Google search) or is it āSanDiskā?
Either way, please post a photo of the card and the package it came in to identify it, thanks!