I have a couple of devices that are 12V over usb-c. The devices themselves are fine, but the wallwarts the mffr provided are just that - 12v over usb-c. No PD. If a device is expecting 5V, there's a healthy chance it'll .. stop expecting 5V.

We blame usb-c for all this, but it does feel like some mffrs are going out of their way to screw it up.