No surround sound on Chromecast Ultra

[Vibrionales]

Describe the bug

When casting to a Chromecast Ultra from the Jellyfin android client only stereo audio is streamed to the Chromecast.

To Reproduce

Cast any file with surround sound to the Chromecast via the Android app.

Expected behavior

Half a year to a year ago on my old server (Jellyfin version I do not know anymore) I had no issue with casting surround sound files to my system. I would still expect Jellyfin to pick up on the surround sound capabilities of the Chromecast Ultra and be able to stream a source with AC3 audio. When reading forum posts 1 2 3 and other issues 743 66 I am now suspecting the support is disabled since the V1.2.0 release looking at #74 and seeing no support for EAC3 or AC3 build in any of the device profiles.

Logs

Log of the ffmpeg stream:
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'file:/mnt/Media/Movies/Dolby Samples/Amaze-Dolby-thedigitaltheater.mp4': Metadata: major_brand : isom minor_version : 512 compatible_brands: isomiso2avc1mp41 creation_time : 1970-01-01T00:00:00.000000Z encoder : Lavf52.94.0 Duration: 00:01:03.55, start: 0.000000, bitrate: 5037 kb/s Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 1920x1080 [SAR 1:1 DAR 16:9], 4395 kb/s, 24 fps, 24 tbr, 24 tbn (default) Metadata: creation_time : 1970-01-01T00:00:00.000000Z handler_name : VideoHandler vendor_id : [0][0][0][0] Stream #0:1[0x2](und): Audio: ac3 (ac-3 / 0x332D6361), 48000 Hz, 5.1(side), fltp, 640 kb/s (default) Metadata: creation_time : 1970-01-01T00:00:00.000000Z handler_name : SoundHandler vendor_id : [0][0][0][0] Side data: audio service type: main Stream mapping: Stream #0:0 -> #0:0 (h264 (native) -> h264 (h264_qsv)) Stream #0:1 -> #0:1 (ac3 (native) -> aac (libfdk_aac)) Press [q] to stop, [?] for help Output #0, hls, to '/cache/transcodes/5df3dc64cfa7969106383697b28dffc8.m3u8': Metadata: encoder : Lavf61.1.100 Stream #0:0: Video: h264, qsv(bt709, progressive), 1280x720 [SAR 1:1 DAR 16:9], q=2-31, 4395 kb/s, 24 fps, 90k tbn (default) Metadata: encoder : Lavc61.3.100 h264_qsv Side data: cpb: bitrate max/min/avg: 4395030/0/4395030 buffer size: 8790060 vbv_delay: N/A Stream #0:1: Audio: aac, 48000 Hz, stereo, s16, 256 kb/s (default) Metadata: encoder : Lavc61.3.100 libfdk_aac Side data: audio service type: main

System:

• OS: Docker
• Browser: Jellyfin Android App
• Jellyfin version: 10.10.5
• Cast Receiver version: Stable
• Cast client: Ultra

Additional context
Chromecast is directly connected to a receiver with surround sound support.
Chromecast settings in google Home are set to EAC3/AC3 surround sound.