I have the exact same issue. It seems like there is an issue with the drivers, and even when I tried forcing CPU decoding and I got same results.
I installed Moonlight using plugin.program.moonlight-qt.
The error logs look like this:
Code
00:00:50 - Qt Info: Executing request: "https://192.168.0.123:47984/appasset?uniqueid=0123456789ABCDEF&uuid=abe0017256ea40078189ee2e70b5cbbe&appid=1093255277&AssetType=2&AssetIdx=0"
00:00:52 - Qt Info: Found "ModeSeven.ttf" at ":/data/ModeSeven.ttf"
00:00:52 - SDL Info (0): Qt UI screen is at (0,0)
00:00:52 - SDL Info (0): SDL found matching display 0
00:00:52 - SDL Warn (0): Failed to create test window with platform flags: Installed Vulkan doesn't implement the VK_KHR_surface extension
00:00:52 - Qt Info: Server GPU: ""
00:00:52 - Qt Info: Server GFE version: "3.23.0.74"
00:00:52 - SDL Info (0): Video bitrate: 10000 kbps
ALSA lib /build/build.LibreELEC-Generic.x86_64-12.2.1/build/alsa-lib-1.2.11/src/pcm/pcm_dmix.c:1000:(snd_pcm_dmix_open) unable to open slave
00:00:52 - SDL Error (0): Failed to open audio device: ALSA: Couldn't open audio device: No such file or directory
00:00:52 - SDL Info (0): Audio channel count: 2
00:00:52 - SDL Info (0): Audio channel mask: 3
00:00:52 - SDL Info (0): V-sync disabled
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:52 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:52 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:52 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:52 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:52 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:52 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:52 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:52 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:52 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:52 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:52 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:52 - SDL Error (5): Could not restore CRTC
00:00:52 - SDL Info (0): Using SDL renderer
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] nal_unit_type: 32(VPS), nuh_layer_id: 0, temporal_id: 0
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] nal_unit_type: 33(SPS), nuh_layer_id: 0, temporal_id: 0
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] nal_unit_type: 34(PPS), nuh_layer_id: 0, temporal_id: 0
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] nal_unit_type: 21(CRA_NUT), nuh_layer_id: 0, temporal_id: 0
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Decoding VPS
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Main profile bitstream
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Decoding SPS
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Main profile bitstream
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Decoding VUI
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Decoding PPS
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Format yuv420p chosen by get_format().
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Output frame with POC 3.
00:00:52 - FFmpeg: [hevc @ 0x55aa5e3c7c40] Decoded frame with POC 3.
00:00:52 - SDL Info (0): FFmpeg-based video decoder chosen
ALSA lib /build/build.LibreELEC-Generic.x86_64-12.2.1/build/alsa-lib-1.2.11/src/pcm/pcm_dmix.c:1000:(snd_pcm_dmix_open) unable to open slave
00:00:52 - SDL Error (0): Failed to open audio device: ALSA: Couldn't open audio device: No such file or directory
00:00:52 - Qt Warning: Failed to open audio device. Audio will be unavailable during this session.
00:00:56 - Qt Info: Found "gamecontrollerdb.txt" at "/storage/.kodi/userdata/addon_data/plugin.program.moonlight-qt/moonlight-home/.cache/Moonlight Game Streaming Project/Moonlight/gamecontrollerdb.txt"
00:00:56 - SDL Info (0): Loaded 405 new gamepad mappings
00:00:56 - SDL Info (0): V-sync disabled
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:56 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:56 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:56 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:56 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Info (0): Trying fallback VAAPI driver paths
00:00:56 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:00:56 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:00:56 - SDL Error (0): Failed to initialize VAAPI: 3
00:00:56 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:56 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:00:56 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:56 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:00:56 - SDL Info (0): Using SDL renderer
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 7(SPS), nal_ref_idc: 3
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 8(PPS), nal_ref_idc: 3
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] Decoding VUI
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] Format yuv420p chosen by get_format().
00:00:56 - FFmpeg: [h264 @ 0x55aa5e3c7c40] Reinit context to 1280x720, pix_fmt: yuv420p
00:00:56 - SDL Info (0): FFmpeg-based video decoder chosen
00:00:56 - SDL Info (0): Encoder configured for 4 slices per frame
00:00:56 - SDL Error (5): Could not restore CRTC
00:00:57 - Qt Info: Found "gamecontrollerdb.txt" at "/storage/.kodi/userdata/addon_data/plugin.program.moonlight-qt/moonlight-home/.cache/Moonlight Game Streaming Project/Moonlight/gamecontrollerdb.txt"
00:00:57 - SDL Info (0): Loaded 405 new gamepad mappings
00:00:58 - Qt Info: Executing request: "https://192.168.0.123:47984/launch?uniqueid=0123456789ABCDEF&uuid=020703c478e74496afc5f03b00d47283&appid=1093255277&mode=1280x720x60&additionalStates=1&sops=1&rikey=REDACTED&rikeyid=REDACTED&localAudioPlayMode=0&surroundAudioInfo=196610&remoteControllersBitmap=1&gcmap=1&gcpersist=0&corever=1"
00:00:59 - Qt Info: Launch response: "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n<root status_code=\"200\"><sessionUrl0>rtspenc://192.168.0.123:48010</sessionUrl0><gamesession>1</gamesession></root>"
00:00:59 - Qt Info: Found matching interface: "eth0" "E0:51:D8:1A:8E:05" QFlags<QNetworkInterface::InterfaceFlag>(IsUp|IsRunning|CanBroadcast|CanMulticast)
00:00:59 - Qt Info: Interface Type: QNetworkInterface::Ethernet
00:00:59 - Qt Info: Interface MTU: 1500
00:00:59 - SDL Info (0): RTSP port: 48010
00:00:59 - SDL Info (0): Initializing platform...
00:00:59 - SDL Info (0): done
00:00:59 - SDL Info (0): Resolving host name...
00:00:59 - SDL Info (0): done
00:00:59 - SDL Info (0): Initializing audio stream...
00:00:59 - SDL Info (0): done
00:00:59 - SDL Info (0): Starting RTSP handshake...
00:00:59 - SDL Info (0): Audio port: 48000
00:00:59 - SDL Info (0): Video port: 47998
00:00:59 - SDL Info (0): Control port: 47999
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Initializing control stream...
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Initializing video stream...
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Initializing input stream...
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Starting control stream...
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Starting video stream...
00:01:00 - SDL Info (0): Video stream is 1280x720x60 (format 0x1)
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Starting audio stream...
ALSA lib /build/build.LibreELEC-Generic.x86_64-12.2.1/build/alsa-lib-1.2.11/src/pcm/pcm_dmix.c:1000:(snd_pcm_dmix_open) unable to open slave
00:01:00 - SDL Error (0): Failed to open audio device: ALSA: Couldn't open audio device: No such file or directory
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Starting input stream...
00:01:00 - SDL Info (0): done
00:01:00 - SDL Info (0): Received first audio packet after 0 ms
00:01:00 - SDL Info (0): Initial audio resync period: 500 milliseconds
00:01:00 - SDL Info (0): Qt UI screen is at (0,0)
00:01:00 - SDL Info (0): SDL found matching display 0
00:01:00 - SDL Warn (0): SDL_CreateWindow() failed with platform flags: Installed Vulkan doesn't implement the VK_KHR_surface extension
00:01:00 - SDL Info (0): Found display mode with desktop resolution: 3840x2160x60
00:01:00 - SDL Info (0): Gamepad 0 (player 0) is: DualSense Wireless Controller (VID/PID: 0x054c/0x0ce6) (haptic capabilities: 0x10000) (mapping: 030057564c050000e60c000000006800 -> 030057564c050000e60c000000006800,*,a:b0,b:b1,back:b4,dpdown:b12,dpleft:b13,dpright:b14,dpup:b11,guide:b5,leftshoulder:b9,leftstick:b7,lefttrigger:a4,leftx:a0,lefty:a1,rightshoulder:b10,rightstick:b8,righttrigger:a5,rightx:a2,righty:a3,start:b6,x:b2,y:b3,touchpad:b15,misc1:b16,crc:5657,platform:Linux)
00:01:00 - SDL Info (0): Recreating renderer for window event: 1 (0 0)
00:01:00 - SDL Info (0): V-sync enabled
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Info (0): Trying fallback VAAPI driver paths
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Error (0): Failed to initialize VAAPI: 3
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Info (0): Trying fallback VAAPI driver paths
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Error (0): Failed to initialize VAAPI: 3
00:01:00 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:01:00 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:01:00 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:01:00 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Info (0): Trying fallback VAAPI driver paths
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Error (0): Failed to initialize VAAPI: 3
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Info (0): Trying fallback VAAPI driver paths
00:01:00 - SDL Error (0): Unsupported VAAPI rendering subsystem: 13
00:01:00 - SDL Info (0): Skipping VAAPI fallback driver names on libva 2.20+
00:01:00 - SDL Error (0): Failed to initialize VAAPI: 3
00:01:00 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:01:00 - SDL Error (0): VDPAU is not supported on the current subsystem: 13
00:01:00 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:01:00 - SDL Error (0): SDL_Vulkan_GetInstanceExtensions() #1 failed: The specified window isn't a Vulkan window
00:01:00 - SDL Info (0): Frame pacing disabled: target 60 Hz with 60 FPS stream
00:01:00 - SDL Info (0): SDL renderer backend: opengles2
00:01:00 - SDL Info (0): SDL renderer backend requires main thread rendering
00:01:00 - SDL Info (0): Using SDL renderer
00:01:00 - SDL Info (0): Using H.264 SPS fixup
00:01:00 - SDL Error (5): Could not restore CRTC
00:01:00 - SDL Error (5): Could not set videomode on CRTC.
00:01:00 - SDL Info (0): FFmpeg-based video decoder chosen
00:01:00 - SDL Info (0): Dropping window event during flush: 6 (3840 2160)
00:01:00 - SDL Info (0): IDR frame request sent
00:01:00 - SDL Info (0): Received first video packet after 600 ms
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 7(SPS), nal_ref_idc: 3
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 8(PPS), nal_ref_idc: 3
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] nal_unit_type: 5(IDR), nal_ref_idc: 3
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] Decoding VUI
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] Format yuv420p chosen by get_format().
00:01:00 - FFmpeg: [h264 @ 0x55aa5e3c7c40] Reinit context to 1280x720, pix_fmt: yuv420p
00:01:00 - SDL Error (5): Could not queue pageflip: -13
00:01:00 - SDL Error (5): Could not queue pageflip: -13
00:01:00 - SDL Error (5): Could not queue pageflip: -13
00:01:00 - SDL Error (5): Could not queue pageflip: -13
00:01:01 - SDL Error (5): Could not queue pageflip: -13
...
From my understanding, I need a legacy version of Libre ELEC to make this work? Or is there any other way?
Thanks!