Bugzilla Bug 108141

ERROR: from element /pipeline0/a52dec0: Internal GStreamer error: pad problem. 
File a bug.
Additional debug info:
gstpad.c(2562): gst_pad_set_explicit_caps: /pipeline0/a52dec0:
failed to negotiate (try_set_caps with "audio/x-raw-float, endianness=(int)1234,
width=(int)32, channels=(int)6, rate=(int)48000, buffer-frames=(int)0,
channel-positions=(GstAudioChannelPosition)< GST_AUDIO_CHANNEL_POSITION_LFE,
GST_AUDIO_CHANNEL_POSITION_FRONT_LEFT, GST_AUDIO_CHANNEL_POSITION_FRONT_CENTER,
GST_AUDIO_CHANNEL_POSITION_FRONT_RIGHT, GST_AUDIO_CHANNEL_POSITION_REAR_LEFT,
GST_AUDIO_CHANNEL_POSITION_REAR_RIGHT >" returned REFUSED)
ERROR: from element /pipeline0/a52dec0: Internal GStreamer error: negotiation
problem.  File a bug.
Execution ended after 1 iterations (sum 405751000 ns, average 405751000 ns, min
405751000 ns, max 405751000 ns).

Reproducible: Always
Steps to Reproduce:
1.
2.
3.

The most pertinent command line I used to generate the error:
$gst-launch-0.8 dvdreadsrc title=1 chapter=1 ! dvddemux name=toto
toto.current_audio ! a52dec ! alsasink

could it be the (in)famous alsasink problem?

http://bugzilla.gnome.org/show_bug.cgi?id=315121

Rhythmbox works fine.
If I use the "device=hw:0' property on the alsasink filter it does refuse to start.
Maybe this bug is related.

this bug does look like the upstream ones that debian users reported.

have you tried this? from (http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=305189)
"
 I suspect this is because alsasink doesn't work "out of the box" with
 your alsa driver.  Please try the following two tests:
 1/ try running the very same pipeline with "! alsasink device=hw:0" at
 the end of the pipeline

 2/ try creating a .asoundrc file in your home directory with the
 following content:
    pcm.!default {
    type hw
    card 0
    }

    ctl.!default {
    type hw
    card 0
    }
 and then try a pipeline with alsasink (without the device= flag).
"

if you already have a .asoundrc, another suggestion was to get rid of it ( move
it ) and try again.

Report back results.  We'll probably follow upstream on this.

With the provided asoundrc file, I get the same error than without the asoundrc
file and with alsasink device=hw:0

$gst-launch-0.8 dvdreadsrc title=1 chapter=1 ! dvddemux name=toto
toto.current_audio ! a52dec ! alsasink device=hw:0
EXECUTION du tube en cours ...
libdvdread: Using libdvdcss version 1.2.9 for DVD access
No accelerated IMDCT transform found

(gst-launch-0.8:7404): GStreamer-WARNING **: element a52dec0 claimed
state-change success,but state didn't change to PAUSED. State is READY (PAUSED
pending), fix the element
ERROR


I suspect a mismatch between my alsa module in kernel 2.6.13-r3 and my alsa
userland... I'm going to recompile all that... if it does work I'll be back
shortly, if not...

Does not work...

Updated to alsa 1.0.10rc2. I got it working with:

gst-launch-0.8 dvdreadsrc location=/dev/hdc ! dvddemux name=foo
foo.current_audio ! a52dec ! audioconvert ! alsasink device=hw:0

I must use the audioconvert filter and must use the device=hw:0(or the .asoundrc
file) parameter in order to make everything work properly.
I tried esdsink... unable to get sound from it.

Gone with alsa 1.0.10rc3

This is not a bug, you need an audioconvert between a52dec and alsasink