Floris, Where do you find the Neutrik box you are talking about with RJ45 and SPDIF connectors, I made a homemade one with those connectors but then I had to buy different adapters and replace the connectors in each end.
I only know about this one https://www.neutrik.com/en/product/naditbnc-f which I used and changed the connector at each end.

Pictures of modified Neutrik with RJ45 and SPDIF in the ends.

RJ45 end
[Linked Image]

SPDIF end
[Linked Image]


TV room: 861v8, 800v4, UHD722,Front 2xDSP7200SE, DSP7200HCSE, Side DSP5200, Rear DSP33, DSW, (DD 15 Sub),
Roon Rock NUC, QNAP NAS, Chromecast Ultra, Apple TV, Oppo BDP-103D, Pro-ject Pre box S2 digital, Philips Pronto remotes, Supra LoRad Power.
Office: 800v3, MS200, DSP3100
Basement: MS600, 502, 557, Dynaudio 52se, Dynaudio Sub 250