[x86-64] Audio Passthrough not working on a N100 System

Hi,

I am on a GMKTEC G5. N100 CPU.

All works except audio passthrough. The mediacenter is directly connected to my Hisense AX5125H soundbar (which supports up to Dolby Atmos, DTS-HD etc), and itself is connected to Hisense U8N via eARC.

I always see that the soundbar only receives PCM despite DTS or DD+ Tracks.

Here is debug log when running a DTS example.

The output HDMI Port seems to support the streaming options:

2024-10-16 10:32:00.095 T:920 info <general>: m_deviceName : hdmi:CARD=PCH,DEV=0
2024-10-16 10:32:00.095 T:920 info <general>: m_displayName : HDA Intel PCH
2024-10-16 10:32:00.095 T:920 info <general>: m_displayNameExtra: HEC HISENSE on HDMI #0
2024-10-16 10:32:00.095 T:920 info <general>: m_deviceType : AE_DEVTYPE_HDMI
2024-10-16 10:32:00.095 T:920 info <general>: m_channels : FL, FR, LFE, FC, BC, BL, BR, FLOC, FROC, BLOC, BROC, TFC, TC, TFL, TFR, UNKNOWN1
2024-10-16 10:32:00.095 T:920 info <general>: m_sampleRates : 32000,44100,48000,88200,96000,176400,192000
2024-10-16 10:32:00.095 T:920 info <general>: m_dataFormats : AE_FMT_RAW,AE_FMT_S32NE,AE_FMT_S16NE,AE_FMT_S16LE,AE_FMT_RAW
2024-10-16 10:32:00.095 T:920 info <general>: m_streamTypes : STREAM_TYPE_AC3,STREAM_TYPE_DTSHD,STREAM_TYPE_DTSHD_MA,STREAM_TYPE_DTSHD_CORE,STREAM_TYPE_DTS_1024,STREAM_TYPE_DTS_2048,STREAM_TYPE_DTS_512,STREAM_TYPE_EAC3,STREAM_TYPE_TRUEHD

From my limited understanding it looks like its not being passed through but reencoded into PCM:

2024-10-16 10:31:49.309 T:1577 info <general>: CDVDAudioCodecFFmpeg::Open() Successful opened audio decoder dca

2024-10-16 10:31:49.309 T:1577 info <general>: Creating audio thread

2024-10-16 10:31:49.924 T:921 debug <general>: CActiveAESink::OpenSink - ALSA Initialized:
2024-10-16 10:31:49.924 T:921 debug <general>: Output Device : HDA Intel PCH
2024-10-16 10:31:49.924 T:921 debug <general>: Sample Rate : 48000
2024-10-16 10:31:49.924 T:921 debug <general>: Sample Format : AE_FMT_S32NE
2024-10-16 10:31:49.924 T:921 debug <general>: Channel Count : 6
2024-10-16 10:31:49.924 T:921 debug <general>: Channel Layout: FL, FR, FC, LFE, SL, SR
2024-10-16 10:31:49.924 T:921 debug <general>: Frames : 2400
2024-10-16 10:31:49.924 T:921 debug <general>: Frame Size : 24

I already read some other threads but couldnt come up with anything.

Thanks

I tried disabling pulseaudio as I read this may help but it did not.

I am unsure now if the passthrough is attempted or not.

I have figured it out me dummy...I just realized now that there is an Expert Menu and all the advanced passthrough options were disabled.

Works fine now.

Recommendation for the dev team: If someone enables passthrough then enable it for all formats by default...it makes no sense I have to go into Expert mode and enable them manually despite the main passthrough being enabled already.

Quote from popcornmix

Not really.

A TV supporting AC3 passthrough is quite common.

A TV supporting DTS passthrough is quite rare.

A TV supporting DTS-HD/TrueHD passthrough is almost unheard of.

Enabling passthrough on a device that doesn't support it, will at best produce silence and possibly loud white noise.

Display More

But then don't hide the options in the first place, maybe im stupid but it didnt occur to me that there even is a hidden 'more options' menu, nor did anyone online ever hint to look there who had issues with passthrough