Playback of live tv channels that are audio only not working

Since I updated to Jellyfin server 10.4 I cannot playback audio only TV channels anymore. “Normal” tv channels (channels with audio and video) play just fine.
There are a bunch of radio stations here that use regular TV channels (you can tune them in TV as any other channel) to broadcast. This channels are audio only, no video. When I try to play any of these channels using Firefox, playback fails and Jellyfin server logs the following:

[2019-10-26 21:45:18.670 +02:00] [INF] User policy for "Fernando". EnablePlaybackRemuxing: True EnableVideoPlaybackTranscoding: True EnableAudioPlaybackTranscoding: True
[2019-10-26 21:45:18.670 +02:00] [INF] Profile: "Unknown Profile", Path: "http://192.168.7.14", isEligibleForDirectPlay: True, isEligibleForDirectStream: True
[2019-10-26 21:45:18.670 +02:00] [INF] Profile: "Unknown Profile", No direct play profiles found for Path: "http://192.168.7.14"
[2019-10-26 21:45:18.670 +02:00] [INF] Opening channel stream from "Emby", external channel Id: "hdhr_5005"
[2019-10-26 21:45:18.670 +02:00] [INF] Streaming Channel hdhr_5005
[2019-10-26 21:45:18.671 +02:00] [INF] GetChannelStream: channel id: "hdhr_5005". stream id: "native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c" profile: "native"
[2019-10-26 21:45:18.671 +02:00] [INF] Opening SharedHttpStream Live stream from "http://192.168.7.14:5004/auto/v5005"
[2019-10-26 21:45:19.187 +02:00] [INF] Beginning "SharedHttpStream" stream to "/var/lib/jellyfin/transcoding-temp/96ac5e9d5cb64b198a0ca9acb487dfd3.ts"
[2019-10-26 21:45:19.188 +02:00] [INF] Live stream opened after 517.072ms
[2019-10-26 21:45:19.188 +02:00] [INF] Returning mediasource streamId "native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c", mediaSource.Id "native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c", mediaSource.LiveStreamId null
[2019-10-26 21:45:19.189 +02:00] [INF] Live tv media info probe took "0.0004081" seconds
[2019-10-26 21:45:19.189 +02:00] [INF] Live stream opened: {"Protocol":"Http","Id":"native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c","Path":"https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts","Type":"Default","Container":"mpegts","IsRemote":false,"ReadAtNativeFramerate":false,"IgnoreDts":true,"IgnoreIndex":false,"GenPtsInput":false,"SupportsTranscoding":true,"SupportsDirectStream":true,"SupportsDirectPlay":false,"IsInfiniteStream":true,"RequiresOpening":true,"RequiresClosing":true,"LiveStreamId":"a17c75760a04e99b68cf766e11316e1c_09efa0d56b934a82adec00a87b837fb0_native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c","BufferMs":0,"RequiresLooping":false,"SupportsProbing":true,"MediaStreams":[{"Codec":"mp2","TimeBase":"1/90000","CodecTimeBase":"1/48000","DisplayTitle":"MP2 stereo","IsInterlaced":false,"ChannelLayout":"stereo","BitRate":128000,"Channels":2,"SampleRate":48000,"IsDefault":false,"IsForced":false,"Type":"Audio","Index":-1,"IsExternal":false,"IsTextSubtitleStream":false,"SupportsExternalStream":false,"Level":0}],"Formats":[],"Bitrate":128000,"RequiredHttpHeaders":{},"AnalyzeDurationMs":3000}
[2019-10-26 21:45:19.190 +02:00] [INF] User policy for "Fernando". EnablePlaybackRemuxing: True EnableVideoPlaybackTranscoding: True EnableAudioPlaybackTranscoding: True
[2019-10-26 21:45:19.190 +02:00] [INF] Profile: "Unknown Profile", Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts", isEligibleForDirectPlay: True, isEligibleForDirectStream: True
[2019-10-26 21:45:19.190 +02:00] [INF] Profile: "Unknown Profile", No direct play profiles found for Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts"
[2019-10-26 21:45:19.190 +02:00] [INF] Profile: "Unknown Profile", Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts", isEligibleForDirectPlay: True, isEligibleForDirectStream: True
[2019-10-26 21:45:19.191 +02:00] [INF] Profile: "Unknown Profile", No direct play profiles found for Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts"
[2019-10-26 21:45:19.191 +02:00] [WRN] HTTP Response 200 to "192.168.7.41". Time (slow): 0:00:00.5226185. "https://jellyfin01:8920/Items/8b22492fad3c3f54d9dfb4b61f112932/PlaybackInfo?UserId=7859effa38cd4a1c93a4b40a041a56a4&StartTimeTicks=0&IsPlayback=true&AutoOpenLiveStream=true&MaxStreamingBitrate=140000000"
[2019-10-26 21:45:19.236 +02:00] [ERR] Could not find handler for "/LiveStreams/MediaInfo"
[2019-10-26 21:45:19.548 +02:00] [ERR] Error processing request
System.NullReferenceException: Object reference not set to an instance of an object.
   at MediaBrowser.Controller.MediaEncoding.EncodingHelper.GetVideoBitrateParamValue(BaseEncodingJobOptions request, MediaStream videoStream, String outputVideoCodec)
   at MediaBrowser.Api.Playback.BaseStreamingService.GetState(StreamRequest request, CancellationToken cancellationToken)
   at MediaBrowser.Api.Playback.Hls.DynamicHlsService.GetMasterPlaylistInternal(StreamRequest request, String method)
   at Emby.Server.Implementations.Services.ServiceExecGeneral.GetTaskResult(Task task)
   at Emby.Server.Implementations.Services.ServiceHandler.ProcessRequestAsync(HttpListenerHost httpHost, IRequest httpReq, HttpResponse httpRes, ILogger logger, CancellationToken cancellationToken)
   at Emby.Server.Implementations.HttpServer.HttpListenerHost.RequestHandler(IHttpRequest httpReq, String urlString, String host, String localPath, CancellationToken cancellationToken)
[2019-10-26 21:45:20.607 +02:00] [ERR] Error processing request
System.NullReferenceException: Object reference not set to an instance of an object.
   at MediaBrowser.Controller.MediaEncoding.EncodingHelper.GetVideoBitrateParamValue(BaseEncodingJobOptions request, MediaStream videoStream, String outputVideoCodec)
   at MediaBrowser.Api.Playback.BaseStreamingService.GetState(StreamRequest request, CancellationToken cancellationToken)
   at MediaBrowser.Api.Playback.Hls.DynamicHlsService.GetMasterPlaylistInternal(StreamRequest request, String method)
   at Emby.Server.Implementations.Services.ServiceExecGeneral.GetTaskResult(Task task)
   at Emby.Server.Implementations.Services.ServiceHandler.ProcessRequestAsync(HttpListenerHost httpHost, IRequest httpReq, HttpResponse httpRes, ILogger logger, CancellationToken cancellationToken)
   at Emby.Server.Implementations.HttpServer.HttpListenerHost.RequestHandler(IHttpRequest httpReq, String urlString, String host, String localPath, CancellationToken cancellationToken)
[2019-10-26 21:45:20.738 +02:00] [INF] User policy for "Fernando". EnablePlaybackRemuxing: True EnableVideoPlaybackTranscoding: True EnableAudioPlaybackTranscoding: True
[2019-10-26 21:45:20.738 +02:00] [INF] Profile: "Unknown Profile", Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts", isEligibleForDirectPlay: True, isEligibleForDirectStream: True
[2019-10-26 21:45:20.738 +02:00] [INF] Profile: "Unknown Profile", No direct play profiles found for Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts"
[2019-10-26 21:45:20.780 +02:00] [ERR] Error processing request
System.NullReferenceException: Object reference not set to an instance of an object.
   at MediaBrowser.Controller.MediaEncoding.EncodingHelper.GetVideoBitrateParamValue(BaseEncodingJobOptions request, MediaStream videoStream, String outputVideoCodec)
   at MediaBrowser.Api.Playback.BaseStreamingService.GetState(StreamRequest request, CancellationToken cancellationToken)
   at MediaBrowser.Api.Playback.Hls.DynamicHlsService.GetMasterPlaylistInternal(StreamRequest request, String method)
   at Emby.Server.Implementations.Services.ServiceExecGeneral.GetTaskResult(Task task)
   at Emby.Server.Implementations.Services.ServiceHandler.ProcessRequestAsync(HttpListenerHost httpHost, IRequest httpReq, HttpResponse httpRes, ILogger logger, CancellationToken cancellationToken)
   at Emby.Server.Implementations.HttpServer.HttpListenerHost.RequestHandler(IHttpRequest httpReq, String urlString, String host, String localPath, CancellationToken cancellationToken)
[2019-10-26 21:45:21.795 +02:00] [ERR] Error processing request
System.NullReferenceException: Object reference not set to an instance of an object.
   at MediaBrowser.Controller.MediaEncoding.EncodingHelper.GetVideoBitrateParamValue(BaseEncodingJobOptions request, MediaStream videoStream, String outputVideoCodec)
   at MediaBrowser.Api.Playback.BaseStreamingService.GetState(StreamRequest request, CancellationToken cancellationToken)
   at MediaBrowser.Api.Playback.Hls.DynamicHlsService.GetMasterPlaylistInternal(StreamRequest request, String method)
   at Emby.Server.Implementations.Services.ServiceExecGeneral.GetTaskResult(Task task)
   at Emby.Server.Implementations.Services.ServiceHandler.ProcessRequestAsync(HttpListenerHost httpHost, IRequest httpReq, HttpResponse httpRes, ILogger logger, CancellationToken cancellationToken)
   at Emby.Server.Implementations.HttpServer.HttpListenerHost.RequestHandler(IHttpRequest httpReq, String urlString, String host, String localPath, CancellationToken cancellationToken)
[2019-10-26 21:45:21.829 +02:00] [INF] User policy for "Fernando". EnablePlaybackRemuxing: True EnableVideoPlaybackTranscoding: True EnableAudioPlaybackTranscoding: True
[2019-10-26 21:45:21.829 +02:00] [INF] Profile: "Unknown Profile", Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts", isEligibleForDirectPlay: True, isEligibleForDirectStream: True
[2019-10-26 21:45:21.829 +02:00] [INF] Profile: "Unknown Profile", No direct play profiles found for Path: "https://127.0.0.1:8920/LiveTv/LiveStreamFiles/96ac5e9d5cb64b198a0ca9acb487dfd3/stream.ts"
[2019-10-26 21:45:21.862 +02:00] [ERR] Error processing request
System.NullReferenceException: Object reference not set to an instance of an object.
   at MediaBrowser.Controller.MediaEncoding.EncodingHelper.GetVideoBitrateParamValue(BaseEncodingJobOptions request, MediaStream videoStream, String outputVideoCodec)
   at MediaBrowser.Api.Playback.BaseStreamingService.GetState(StreamRequest request, CancellationToken cancellationToken)
   at MediaBrowser.Api.Playback.Hls.DynamicHlsService.GetMasterPlaylistInternal(StreamRequest request, String method)
   at Emby.Server.Implementations.Services.ServiceExecGeneral.GetTaskResult(Task task)
   at Emby.Server.Implementations.Services.ServiceHandler.ProcessRequestAsync(HttpListenerHost httpHost, IRequest httpReq, HttpResponse httpRes, ILogger logger, CancellationToken cancellationToken)
   at Emby.Server.Implementations.HttpServer.HttpListenerHost.RequestHandler(IHttpRequest httpReq, String urlString, String host, String localPath, CancellationToken cancellationToken)
[2019-10-26 21:45:22.881 +02:00] [ERR] Error processing request
System.NullReferenceException: Object reference not set to an instance of an object.
   at MediaBrowser.Controller.MediaEncoding.EncodingHelper.GetVideoBitrateParamValue(BaseEncodingJobOptions request, MediaStream videoStream, String outputVideoCodec)
   at MediaBrowser.Api.Playback.BaseStreamingService.GetState(StreamRequest request, CancellationToken cancellationToken)
   at MediaBrowser.Api.Playback.Hls.DynamicHlsService.GetMasterPlaylistInternal(StreamRequest request, String method)
   at Emby.Server.Implementations.Services.ServiceExecGeneral.GetTaskResult(Task task)
   at Emby.Server.Implementations.Services.ServiceHandler.ProcessRequestAsync(HttpListenerHost httpHost, IRequest httpReq, HttpResponse httpRes, ILogger logger, CancellationToken cancellationToken)
   at Emby.Server.Implementations.HttpServer.HttpListenerHost.RequestHandler(IHttpRequest httpReq, String urlString, String host, String localPath, CancellationToken cancellationToken)
[2019-10-26 21:45:22.897 +02:00] [INF] Playback stopped reported by app "Jellyfin Web" "10.4.0" playing "EUROPA FM". Stopped at "0" ms
[2019-10-26 21:45:22.904 +02:00] [INF] Live stream "native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c" consumer count is now 0
[2019-10-26 21:45:22.904 +02:00] [INF] Closing live stream "a17c75760a04e99b68cf766e11316e1c_09efa0d56b934a82adec00a87b837fb0_native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c"
[2019-10-26 21:45:22.904 +02:00] [INF] Closing "SharedHttpStream"
[2019-10-26 21:45:22.904 +02:00] [INF] Live stream "a17c75760a04e99b68cf766e11316e1c_09efa0d56b934a82adec00a87b837fb0_native_31c961d9e8e85ab8abd8f45ec8471a9f_d6aa108e8cce3615994c44f351de336c" closed successfully
[2019-10-26 21:45:22.905 +02:00] [INF] Deleting temp files ["/var/lib/jellyfin/transcoding-temp/96ac5e9d5cb64b198a0ca9acb487dfd3.ts"]

Before upgrading to 10.4 playback of these channels was working fine.
Deployment details:

OS: Debian 10 (Buster)
Jellyfin server version: 10.4
Firefox version: 70.0
Hardware details: VM 4 vCPUs, 3GB RAM. HDHomerun Connect (HDHR4-2DT)

Thanks.

Hrm… Seems that the FFmpeg implementation is looking for a video codec, and one isn’t being reported. This would be great to file as an issue on GitHub, if you don’t mind… I can also fill it out if you’re not able to.

Thanks for the reply. I will open an issue in Github.

I just opened the issue in Github: https://github.com/jellyfin/jellyfin/issues/1957

Thanks.