After adding all the gizmos (VHF/UHF DMR/Analog radio, ethernet intranet, APRS I-Gate, DMR Hotspot, LTE access) I suddenly had full scale RFI on some VHF frequencies.
So from a fully functional radio system, intranet and internet system functioning in harmony it went to a VHF noise floor high enough to make the VHF radio next to unusable. By process of elimination, the only difference was the addition of a MOXA EDS-305 10-48Vdc ethernet switch.
New shielded CAT7 cables has been ordered.
More information about the projected at RF NOISE IN THE CAR