Questions about confusing HDMI audio config / behavior
#1
XMBC 12.0 linux connected from Nvidia GT210 via HDMI to a Panasonic LCD TV (2012 L37ETW5W).

Q1: Do i understand the output of ALSAs ELD data correct right ?: The TV only accepts 2 channel 16 bit 2 channel audio (but not eg: AC3 or DTS).

Code:
cat /proc/asound/card1/eld#1.0
monitor_present         1
eld_valid               1
monitor_name            Panasonic-TV

connection_type         HDMI
eld_version             [0x2] CEA-861D or below
edid_version            [0x3] CEA-861-B, C or D
manufacture_id          0xa934
product_id              0xc328
port_id                 0x20000
support_hdcp            0
support_ai              0
audio_sync_delay        0
speakers                [0xffff] FL/FR LFE FC RL/RR RC FLC/FRC RLC/RRC FLW/FRW FLH/FRH TC FCH
sad_count               1
sad0_coding_type        [0x1] LPCM
sad0_channels           2
sad0_rates              [0xe0] 32000 44100 48000
sad0_bits               [0x20000] 16
[/quote][/code]

XBMC lets me configure all type of confusing audio options, under "Audio output" "Analog", "Optical/Coax", "HDMI" and "Audio output device"/"Passthrough output device". It took me a while to figure out that the "Audio output" selection doesn't seem to do anything more useful than to grey out some of the further options not applicable to that type of connection.

Q2: Why is this config not made more simple ? FOr example, when i do select the "Audio output device"/"Passthrough Device" to be this HDMI device, then XBMC should be able to see from the eld information (see above), that this is a HDMI device (could auto-set 'audio output' to HDMI), and that it only support 2-channel LPCM (could audio-grey-out all the passthrogh options for example, or somehow represent the information from the ELD file so i know what the connected TV supports without going to the linux shell. Took me quite a while to figure out that i had to unselect "AC3 capable receiver/DTS capable receiver" to get any audio from movies with those audio format.

worse: I have also an RPI with XBMC 12.0 connected to the same TV set, and it plays back audio when i select "AC3 capable receiver/DTS capable receiver", so i continuously thought my linux PC has a problem because i do not hear AC3/DTC audio when i enable these options on the linux PC, but it works fine on the RPI. But the RPI must be doing something more different, like automatic software decoding of DTS/AC3 maybe in the driver. Not sure. . Doesn't seem to be using ALSA.

Thanks!
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