[pulseaudio-discuss] Buzzy noise on HDMI using passthrough

[Thomas Martitz]

Am 14.05.2015 um 13:31 schrieb Arun Raghavan:
> On 12 May 2015 at 12:44, Thomas Martitz <kugel at rockbox.org> wrote:
>> Hello,
>>
>> I've got a problem with new TV connected to a Zotac ZBOX with AMD APU via
>> HDMI. When playing movies in Kodi using the pass through option I can hear
>> only buzzy/white noise. The same setup worked fine on my previous TV.
>> However, if I use ALSA, then kodi and audio passthrough works just fine
>> (with either TV).
>>
>> Does anyone know what's wrong here? I first thought the TV is broken, but
>> then how can it work with alsa?
>>
>> I attached the output of pactl list and aplay -L. If I can provide more
>> information just tell me. Pulseaudio version is 6 from debian sid.
>>
>> PS: I did select the "Digital Stereo (HDMI) Output" card profile because I
>> know passthrough does not work in multichannel configurations.
> White noise probably means that what's being sent out is not valid
> data, and is being interpreted as PCM. The logs you sent suggest
> nothing wrong.
>
> Does this work for you (you can get an AC3 file here -
> http://samples.mplayerhq.hu/A-codecs/AC3):
>
>    gst-launch-1.0 filesrc location=/a/file/with/ac3 ! ac3parse ! pulsesink
>

Thanks for the reply. I'll try your suggestion when I get back home. 
However I also tried test files (DD and DTS) in VLC (with pulseaudio 
backend) and the same issue occured.

Strangely, the DTS test file also produced the noise even though the TV 
cannot pass through DTS data. The same file with ALSA backend gives 
silence as expected (and the DD one gives DD sound).

Best regards