@audioman58 said:
which btw digital is not grounded
But the chassis of equipment the shielded ethernet cable plugs into may be. I’ve read posts where a shielded ethernet cable caused a ground loop hum. (Had nothing to do the 4 twisted pairs of the cable.) My understanding the shield is connected at both ends of the cable to the ground metal shell of the RJ45 male connectors. Example of a shielded Cat6a RJ45 plug
If the equipment manufacturer didn’t install a RJ45 jack that is a grounding type, bonded to chassis, then a path to chassis ground is not provided.
FWIW a shield, Faraday cage, does not need to be grounded to work.YMMV
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