With HDMI or USB3.0/3.1, a cable assembly, in addition to the main braided shield, has multiple separate shields for each differential pair, here an example of a USB3.0 cable:
The inner shields are connected to the
GND_Drain pin on the plug:
With HDMI, it's even more complicated. There, every single one of the four differential signal pairs has its own ground connection on the plug:
How am I supposed to connect these additional ground connections together on a device? Coming from this question, the outer shield could be connected to power ground directly - a few more options are outlined here - and should be connected to the case of my device if that's made from metal. That's easy enough, but what about these additional connections? Would connecting them directly to the outer shield reduce their effectiveness?