This is exactly what happens when the logic high output level of the 3.3V Omega2 is just at the minimum level for 5V WS2813 to be recognized.
For testing, it might help to lower the 5V supply a tiny bit (4.9V instead of 5V, easy to try if you have a lab power supply), because this also lowers the logic high threshold of the WS2813 chips a bit.
A logic level converter is certainly the way to go to make that reliable - but the type you chose is most certainly way too slow for the WS2813 signal. These bi-directional thingies are good for serial speeds (many offers do not properly spec, but those that do say max 28800bd). The WS281x signal is in the 1mbps range, however.
For that you want to use a unidirectional level shifter, such as the 74AHCT125 (or its single-gate version, 74AHCT1G125). I used that one successfully for my "pixelboard", see schematics, with 200 WS2813.
So after seeing the recent updates about SPI one of my bugs is fixed. However this isn't.
I've been able to cross compile the software by applying a patch in the toolchain however I also need to install the patched libc on the onion omega of which when I force it to do so it bricks it and requires firmware recovering.
I then uploaded what I believe was the firmware compiled by the toolchain however that then caused SPI To break again and have packages such as gpioctl missing.
Is there any recommendation on what packages need to be selected to have most things required?
@George-Gerber, it is there, you may miss it because it falls under 0.1.10 i.e. omega2p-v0.1.10-b160.bin
@Sergiy-Tarasov, I have had some success using what is most likely a hack and not recommended.
Uncomment line 1 "reboot_core" in the file /etc/opkg/distfeeds.conf
opkg --force-depends install kmod-i2c-gpio-custom
Now the hack, because it was for a higher kenel version the libraries are installed to /lib/module/<kenel-version> so we need to copy them across to the current version, in my case:
cp /lib/modules/4.4.131/* /lib/4.47/
@Maximilian-Gerhardt wow! Thank you very much for your response, at least I don't have the feeling like I'm shouting into an empty cave!
I'm surprised at how beta the i2c library is for something that's been out for ~years. I feel like the first feature for boards like this (after GPIO control on its own pins) should be a matured and robust i2c library. Since, almost anything you want to do with them will require i2c communication...
Again, thank you for the heads up with known issues. I'll try to keep stumbling through this and if I succeed I'll make it available.