[MPlayer-dvb] On HD Channels no audio!

[Raena Lea-Shannon]

I can get passthrough working OK with DVDs with ALSA using mplayer. That 
config file tip is very handy thankyou. Would it work the same if you 
had ac=hwafm?

I have IEC958 set up OK using alsamixer gui. I don't go near the 
asoundrc file as that ALSA kung fu is way passed me.

I don't think it is a bad channel just a bad channels.conf file I hope. 
But that is a very neat tip for bad channels.

Thankyou.

Bill Pringlemeir wrote:
> On 24 Oct 2009, Raena Lea-Shannon <raen at internode.on.net> wrote:
> 
>> I have checked the list archives, google and gmane search on mplayer and
>> I have updated by channels conf file with scan  and I have tried 
>> inserting :pid[8192] into in the audio/video field in the channels.conf 
>> file and I have checked mplayer -ac help and a53 and ac3 and passthrough 
>> hwac3 are all ok and still no audio! just on the HD Channels.
> 
> I have the following in my '~/.mplayer/config'
> 
> # Use alsa drivers.
> #ao=alsa
> ao=alsa:device=plug=spdif
> #channels=6 
> ac=hwac3,hwdts,a52,
> 
> Are you using an spdif passthru?  This is what 'hwac3' is for.  If you
> have this, you need to modify alsa.
> 
>  amixer -c 0 sset 'IEC958 Optical Raw' on
> 
> There is something wrong with the SVN version of mplayer and the
> latest (or some versions) of alsa libs.  There is an "AES=6" parameter
> that is sent to alsa when running in passthrough mode.  This is
> incorrect.  There is some crazy langauge with alsa and there is a
> '.asoundrc' file.  Mine is like this,
> 
>     ##<confdir:/usr/share/alsa/pcm/iec958.conf>
>     pcm.!default {
>         type plug
>         slave.pcm "iec958:CARD=Live,DEV=0"
>     }
> 
> The alsa configuration language is very complex (and powerful), but it
> can be a bit of a barrier to entry.
> 
> Running this via SPDIF to a Sony AMP lets me received the AC3
> channels.  There are various problems with the AC3 feeds from various
> stations; if you see a station switching from 5/2 to 2 channels,
> etc. There may be occasions that the sound via passthru will be
> rejected by your AMP (or whatever you are using).  You can try the
> following to ~/.mplayer/config,
> 
> [messed-up-channel]
> #af-add=volume=3
> af-add=surround
> af-add=sub=50:5
> af-add=center
> af-add=lavcac3enc=1:448:2
> 
> and then run 'mplayer -profile messed-up-channel dvb://bad-channel'.
> This method seems to produce better results, but the rear channels are
> always mixed together.  With the passthrough, the rear channels are
> completely seperate which is occasionally an interesting effect.
> 
> My reception is OTA and the last stuff about channel switching might
> be paranoia and it is just BER effects.  However, I have seen others
> report similar problems with different OS/programs.
> 
> Some one also reported an issue about the amount of buffering and
> mplayer going crazy when the buffer is depleted with OTA signals.
> This will also happen for any marginal channel.  The
> linux-dvb-apps/util/szap/femon program can help to see if you have
> problems.  BER values are ok, but if the signal lock goes then you
> won't have luck viewing that channel with mplayer (or possibly
> anything).
> 
> I am running Debian Lenny, so I think that should be close to what you
> have.
> 
> hth,
> Bill Pringlemeir.
> 
> SPDIF==IEC958 ~== AC3 passthru
>