Recommendations for a 4K supporting Kodi box with SPDIF for Audio

I have been through the start here thread and didn’t see anything that ticked all the boxes for me.

My background – I have a 4k TV that only has a single HDMI 2.0 socket, said TV ( Panasonic 50ax802) doesn’t support 10bit 4k either. Therefore all my 4k devices connect to that one socket via a 4k HDMI switch. However, I also have a Marantz Home Theatre amp for the Audio but whilst it supports 4k, it doesn’t support HDCP 2.2 which makes it next to useless because my Sky Q STB will not connect to it and output 4k as it looks for HDCP 2.2

So in an ideal world, I need a box that runs Kodi, supports 4k output but also includes an SPDIF socket so i can route the audio to my home theatre amp, whilst the HDMI connects to the TV via the switch.

I have been using a Minix NEO x8-h Plus, however it seems to struggle with a number of media types depending on the encode and bitrate

As for price, I am willing to spend a reasonable some, but just not as much as it would cost to build a reasonable HTPC that ticks all these boxes, therefore is there an android/OSMC box that will do what I need but has a bit more grunt and perhaps even runs on a better supported version of android and Kodi?