Frigate Hardware Acceleration - GPU Passthrough

I’m currently running Frigate on an LXC container inside Proxmox (with Home Assistant on a separate VM).

I’m trying to enable GPU passthrough - but getting stuck on a couple of areas.
The notes on the LXC container are showing ‘USB passthrough VAAPI hardware transcoding’.

When I go to the Frigate console and type ls /dev/dri it is showing ‘renderD128’.

However, when I include the following code in the Frigate config file I’m getting the errors thrown up below:

ffmpeg:
  hwaccel_args: preset-vaapi

Errors are as follows:

2025-05-28 13:49:21.364712  [2025-05-28 13:49:21] frigate.util.services          ERROR   : Unable to poll vainfo: b"error: XDG_RUNTIME_DIR is invalid or not set in the environment.\nerror: can't connect to X server!\nerror: failed to initialize display\n"
2025-05-28 13:49:21.524605  [2025-05-28 13:49:21] frigate.util.services          ERROR   : Unable to poll intel GPU stats: No device filter specified and no discrete/integrated i915 devices found
2025-05-28 13:49:43.491755  2025-05-28 13:49:21.525012
2025-05-28 13:49:22.916672  [2025-05-28 13:49:22] frigate.video                  ERROR   : ReolinkDoorbell_rtsp: Unable to read frames from ffmpeg process.
2025-05-28 13:49:22.917613  [2025-05-28 13:49:22] frigate.video                  ERROR   : ReolinkDoorbell_rtsp: ffmpeg process is not running. exiting capture thread...
2025-05-28 13:49:40.227093  [2025-05-28 13:49:40] watchdog.ReolinkDoorbell_rtsp  ERROR   : Ffmpeg process crashed unexpectedly for ReolinkDoorbell_rtsp.
2025-05-28 13:49:40.227567  [2025-05-28 13:49:40] watchdog.ReolinkDoorbell_rtsp  ERROR   : The following ffmpeg logs include the last 100 lines prior to exit.
2025-05-28 13:49:40.227990  [2025-05-28 13:49:40] ffmpeg.ReolinkDoorbell_rtsp.detect ERROR   : [AVHWDeviceContext @ 0x5b95165e85c0] No VA display found for device /dev/dri/renderD128.
2025-05-28 13:49:40.228395  [2025-05-28 13:49:40] ffmpeg.ReolinkDoorbell_rtsp.detect ERROR   : Device creation failed: -22.
2025-05-28 13:49:40.228742  [2025-05-28 13:49:40] ffmpeg.ReolinkDoorbell_rtsp.detect ERROR   : [h264 @ 0x5b95165e7d80] No device available for decoder: device type vaapi needed for codec h264.
2025-05-28 13:49:40.229039  [2025-05-28 13:49:40] ffmpeg.ReolinkDoorbell_rtsp.detect ERROR   : Device setup failed for decoder on input stream #0:0 : Invalid argument
2025-05-28 13:49:42.886465  [2025-05-28 13:49:42] frigate.video                  ERROR   : ReolinkDoorbell_rtsp: Unable to read frames from ffmpeg process.
2025-05-28 13:49:42.886824  [2025-05-28 13:49:42] frigate.video                  ERROR   : ReolinkDoorbell_rtsp: ffmpeg process is not running. exiting capture thread...

Just to note that the following is also included in the config file:

detectors:
  ov:
    type: openvino
    device: CPU

model:
  path: /openvino-model/FP16/ssdlite_mobilenet_v2.xml
  width: 300
  height: 300
  input_tensor: nhwc
  input_pixel_format: bgr
  labelmap_path: /openvino-model/coco_91cl_bkgr.txt

Any ideas?