No display out with One V3 NVME


I’m attempting to get a V3 NVME case with an RPi 5 working. I just can’t seem to get any display out of the thing.

The Pi works fine out of the V3 case, via Micro HDMI adaptor on an HDMI cable, booting from SD card into RPi OS.
Power adaptor: official RPi 27W.

When in the V3 case using the same HDMI cable without the adaptor, the green activity light on the Pi indicates loading, then goes static green, flickering occasionally, so I’m presuming the Pi has booted successfully. The display sees no signal and goes into standby.

I’ve checked a few times the daughterboard being pushed all the way in and that seems to be true, with the boards screwed into the case.

I’ve tried with and without the NVME drive installed (WD Blue SN580), with no difference in behaviour seen.

Any thoughts on what else I can try? TIA!