24v to 12v buck converter issue?

I am in the process of putting up 12v ws2811 string lights on my house using the dig-octa and a 12v 60A power supply for majority of the the lights. On the far end of the house, the distance is too far and the voltage drop is too great to power from the 12v supply. I elected to use a separate 24v power supply with 12awg wire with a 24v to 12v buck converter as the end. The lights are flashing very sporadically no matter what I try to do. Im getting 12v at the end of the buck converter, and again this is a separate power source than the rest of the 12v lights on the house. The only common is the data wire that goes back to the dig octa which is powered from my 12v power supply. Not sure if this is a buck converter issue or the data line getting interferance?

I’ve got this type of setup in a number of places with no issues.

Is there common ground between 24V, 12V, and the buck converters (there should be)?
What’s the maximum data line distance between the strIps and to the dig octa?

I’d make sure you have common grounds 1st and then look at Long Data Lines in the KB.

Thanks for the response. I do have all power supplies, lights and buck converter on the same common ground. The longest stretch of data line i have from the dig octa to the first led is about 30m. I have exprimented by shorting all data and power lines to less than 5 feet so that I can rule out it being a distance issue. The lights respond to turning off and on with the wled app, but when i select solid color for instance, the lights will be all different colors and sometimes flickering. When I select different effects, sometimes they might start working correctly but then go back to sporadically flickering.