[mythtv-users] MythTV 0.24 HDMI audio problem

[Jarod Wilson]

On Dec 9, 2010, at 12:35 PM, James Courtier-Dutton wrote:

> On 7 December 2010 05:33, John P Poet <jppoet at gmail.com> wrote:
>> On Mon, Dec 6, 2010 at 7:19 AM, Jean-Yves Avenard <jyavenard at gmail.com> wrote:
>>> Hi Jarod
>>> 
>>> On 20 November 2010 17:03, Jarod Wilson <jarod at wilsonet.com> wrote:
>>>> On Nov 19, 2010, at 8:05 PM, Jean-Yves Avenard wrote:
>>>> 
>>>>> On 20 November 2010 08:36, Jarod Wilson <jarod at wilsonet.com> wrote:
>>>>>> sure if its directly related or not, but scanning for audio
>>>>>> devices tends to always segfault on this box too. Same build
>>>>>> works just fine on an ion box.
>>>>> 
>>>>> Great, can you put a backtrace on trac ?
>>>> 
>>>> Yeah, I should be able to do that this weekend. Is there a ticket already
>>>> opened that I should tack it onto, or shall I open a new one?
>>>> 
>>>>>> (nVidia 260.19.21 driver, ALSA 1.0.23 kernelspace and userspace).
>>>>> 
>>>>> Did you try the last suggestion of using ALSA:hdmi:CARD=NVidia,DEV=x ?
>>>> 
>>>> Yep. Still no sound. Silence is NOT golden in this case... ;)
>>>> 
>>> 
>>> Well, I received my new audio receiver for my cinema room.
>>> So the first thing I did was installed the GT220 card in the PC
>>> (identical one to my other machine)..
>>> 
>>> Started.. and ... no sound
>>> 
>>> I've finally tracked the issue.
>>> 
>>> Following the steps I had written on how to achieve judder-free
>>> playback, I had totally overridden the EDID with Option "UseEDID"
>>> "false"
>>> 
>>> Well, this is what caused no sound for me.
>>> 
>>> I replaced it with:
>>>    Option "UseEDIDFreqs" "FALSE"
>>>    Option "UseEDIDDpi" "FALSE"
>>>    Option "ModeValidation" "NoEdidModes"
>>> 
>>> (which according to nvidia is the same), and I get audio ...
>>> 
>>> I guess UseEDID disables audio over hdmi as the nvidia drivers aren't
>>> able to check if the display supports sound.
>>> (note that without  Option "ExactModeTimingsDVI" "True" , one of my
>>> custom modelines were working)
>>> 
>>> I thought you could be having the same issue
>>> Jean-Yves
>> 
>> I now have a HDMI equipped pre-amp, so now I am trying to get sound to
>> work.  Unfortunately, the EDID stuff does not seem to be my problem.
>> 
>> What is interesting, is that "aplay -l" lists three HDMI devices:
>> 
>> # aplay -l
>> **** List of PLAYBACK Hardware Devices ****
>> card 0: NVidia [HDA NVidia], device 3: NVIDIA HDMI [NVIDIA HDMI]
>>  Subdevices: 0/1
>>  Subdevice #0: subdevice #0
>> card 0: NVidia [HDA NVidia], device 7: NVIDIA HDMI [NVIDIA HDMI]
>>  Subdevices: 1/1
>>  Subdevice #0: subdevice #0
>> card 0: NVidia [HDA NVidia], device 8: NVIDIA HDMI [NVIDIA HDMI]
>>  Subdevices: 1/1
>>  Subdevice #0: subdevice #0
>> card 0: NVidia [HDA NVidia], device 9: NVIDIA HDMI [NVIDIA HDMI]
>>  Subdevices: 1/1
>>  Subdevice #0: subdevice #0
>> 
>> "aplay -L" just lists one:
>> 
>> # aplay -L
>> null
>>    Discard all samples (playback) or generate zero samples (capture)
>> hdmi:CARD=NVidia
>>    HDA NVidia, NVIDIA HDMI
>>    HDMI Audio Output
>> 
>> If I try to do "speaker-test -Dhdmi:CARD=NVidia" it says that it is
>> producing audio, but I don't hear anything.
>> 
>> If I add a bit to my /etc/asound.conf file:
>> 
>> ~~~~~~~~~~~~~~~~~~~~~~~
>> pcm.nvidia_hdmi {
>>  type plug
>>  slave {
>>    pcm "hw:0,7"
>>  }
>> }
>> 
>> pcm.!default nvidia_hdmi
>> pcm:iec958 nvidia_hdmi
>> ~~~~~~~~~~~~~~~~~~~~~~~
>> 
>> Then *just* type "speaker-test", I *DO* get sound!  At this point, I
>> can use aplay to play wav files.
>> 
>> Note, that if I change the asound.conf file to have:
>>  pcm "hw:0,3"
>> Then I don't get any sound.  with "hw:0,7", "hw:0,8" and "hw:0,9" I
>> *do* get sound.
>> 
> 
> For those interested.
> For hdmi and ALSA, use device names like the following:
> hdmi:0,0
> hdmi:0,1
> hdmi:0,2
> hdmi:0,3
> 
> For my setup, hdmi:0,1 is the only one that works.
> 
> No need to use hw:0,7 and such like.

Finally got back to poking at my GT220 tonight. I've finally successfully
gotten audio off the thing using aplay, but the *only* device that works
is plughw:x,y (x=1, y={3,7,8,9} all work, in this case). hw:x,y results
in "Channels count non available", as does hdmi:CARD=NVidia and hdmi:1,0.
hdmi:1,{1-3} all result in "No such file or directory". On to poking via
mythtv next...

Not sure if updating to the nVidia 260.12.29 drivers mattered, prior
poking at the card was with 260.12.21, iirc, but it seems something still
isn't quite right here. Getting closer, at least.

-- 
Jarod Wilson
jarod at wilsonet.com