In German it’s called Arschbackenoberschenkelabtrennfalte
In German it’s called Arschbackenoberschenkelabtrennfalte
There are other fast charging standards than Power Delivery. USB Battery Charging defines that when the data lines are shorted, a device can draw more current (up to 1.5A), but still at 5V. QuickCharge on the other hand uses the data lines to negotiate higher voltages, so an A-to-C cable can’t protect you from that.
For Power Delivery, higher voltages are negotiated using the CC (configuration channel) pins. If you use an A-to-C cable, the A side does not have the CC pins and therefore you can’t get more than 5V.
Have you checked what voltage arrives on the board if you use a regular USB-C charger? Maybe the headphones negotiate and need a higher voltage than 5V. Does it charge with only 5V supplied? (could be forced by using an A-to-C cable in case of Power Delivery)
I noticed that you use digitalWrite multiple times for each transmitted pixel. That function is pretty slow - you should instead manipulate the microcontrollers registers directly for maximum performance. If you are using an Arduino, this article will help: https://roboticsbackend.com/arduino-fast-digitalwrite/