SOLVED: Hardware Acceleration issue

[nnb]

I got an Nvidia P400 graphic card to use for hardware acceleration but I'm not having success (I think).

My Setup:
CPU: Intel i7-8700
GPU: Quadro P400
Ram: 16GiB
OS: Ubuntu 22.04.4 LTS 64b
Jellyfin.Server 10.9.11.0
For testing, I'm using Brave Browser as a client

I believe I have the nvidia-driver-550 installed (by checking ubuntu update-> additional Driver)
   

When I run nvidia-smi I get this, which I believe is an indication that the driver is rightly installed:
   

To verify that if I'm using hardware acceleration (or not), I'm using htop.
When I have hardware acceleration (in Jellyfin) set to None, and I play a video, it all goes to 100% as expected.
nvidia-smi doesn't show anything different.

When I select Nvidia NVENC (with only HVEC 10bit and VP9 10bit UNselected) for decoding AND Hardware encoding options-> Enable hardware encoding UNselected, and I play a video, the CPU goes to ~100% like before, but I get a new line in nvidia-smi:
   

As soon as I select Hardware encoding options-> Enable hardware encoding, doesn't matter which options for "Enable hardware decoding for" I have selected, as soon as I try to open a video, I get "Playback Error - Playback failed due to fatal player error.

Is this expected?
I would expect the CPU to be much lower when using a GPU. (Is the GPU even being used at all?)

I appreciate any help
Thanks