TV not seeing 12TB G-Raid drive on HDMI connection

I have a Canon R5 camera which I use for 4k 50fps video. Connecting the camera directly to my Sony 4K Android TV via its HDMI port, the video plays perfectly well but this is not very convenient. I bought a 12TB G-Raid unit to store the video files and play them directly on the TV via the G-Raid HDMI link. Although the TV can see the connection it reports No Signal on the link. It can see the G-Raid and its files when I connect using the USB port but the video runs far too slowly to be of any use. Is there something I have not understood about the HDMI connection; do I need to activate the port in some way; is the G-Raid capable of doing what I want? I have tried different cables and use VLC on the TV to handle the video.

Hi @DavidDale,

Please contact the WD Technical Support team for best assistance and troubleshooting:
https://support-en.wd.com/app/ask