9 Replies Latest reply on May 24, 2014 9:25 AM by slackhead

    Wolfson Audio Card - no SPDIF out.

    slackhead

      I'm on my 2nd Wolfson card as I sent the first back thinking it was broken.

      I just cannot get any output from SPDIF, not even with the example HD flacs. Lineout works fine.

      I'm using mplayer -ao alsa to play flacs. There are no errors in output. Same with aplay. No errors but no sound.

      I'm using a 32G class 10 SD card.

      I've tried the pre-built wolfson kernel and also patched my own.

      I'm not using an external power source as I understand that that's is just needed for speaker output?

       

      I see a few errors and tracebacks in dmesg. Link to dmesg output:

       

      http://www.r0t.co.uk/paste/p/78wvTi31.html

       

      I'm beginning to wonder if it's the actual Pi that's faulty, but it seems OK for everything else.

       

      Now this is the strange part: I get SPDIF out if there is a line out cable plugged in with a load across it - ie plugged into my hifi preamp.

      If I pull the plug either end then SPDIF stops. I can verify that I am actually listening to the SPDIF output by turning off my DAC, and also the preamp selector switch is on input 1 for SPDIF and 4 for line in, so there is no way that the lineout signal is getting through. If I switch to the input that lineout is connected to, there is no output.

       

      Any ideas?

       

      Incidentally, both cards showed exactly the same symptoms.

        • Re: Wolfson Audio Card - no SPDIF out.
          tyres2

          Hi,

           

          I've been using the Wolfson card, with SPDIF out, for quite  a few months now. Very happy with it, and no problems. You don't say whether you are using it via the Pi desktop, or using it headless?

           

          I use it headless. Originally I tried it with the Squeezeplug distribution, which I think worked. I had previously been using a USB DAC with the Raspyfi distribution, and I found a way of using that with the Wolfson, by using Ragnar Jensen's custom Wolfson kernel. That's what I still use, and it performs very well.

            • Re: Wolfson Audio Card - no SPDIF out.
              slackhead

              Yeah I'm headless too. It's fine that yours works as expected. I'm using armed slack and I won't be changing distros because of this. My DAC is a SMSL SD-1955 which has a max of 24bit 192K, so it should play back anything thrown at it.

               

              I'm using Ragnar Jensen's custom Wolfson kernel too at the moment, while I'm waiting for a new one to finish off in qemu, then I'll switch to that.

               

              I'm wondering if the use_case_scripts are old and maybe I need to try out some new ones? Do you have a link to the ones that you are using?

                • Re: Wolfson Audio Card - no SPDIF out.
                  tyres2

                  Hi,

                   

                  I don't know what the 'armed slack' is. I think the Raspyfi distribution i'm using is essentially Raspian with some tweaks to improve audio output, generally based on 'mpd' as the player. The 'use-case' scripts I'm using are the ones that Ragnar included with his 'stripped-down' version of the Wolfson download. So I'd imagine you've probably got those already.

                   

                  I'd guess the problems you are having may be something to do with using 'armed slack', so I'm not sure how you get round that. Or maybe the problem is the player? How about trying a different player? Like MPD. At least just to prove that you 'can' get sound out via SPDIF-out.

                    • Re: Wolfson Audio Card - no SPDIF out.
                      slackhead

                      Armed Slack = Slackware for Arm, basically.

                       

                      I have the same problem playing a wav with aplay so I know it isn't mplayer.

                       

                      This seems to be a problem with connecting outputs to inputs internally. I will probably test a few different loads on the line out to see what works and what doesn't. I did have a quick look through alsamixer to see what was connected to what, but I haven't thoroughly tested.

                        • Re: Wolfson Audio Card - no SPDIF out.
                          tyres2

                          Dave Wood wrote:

                           

                          Armed Slack = Slackware for Arm, basically.

                           

                           

                          OK. I didn't know that was still around. I think I used that back in the 90s (Slackware)! It must be one of the oldest distros around.

                           

                          If you have a spare SD card it might be worth trying another distro, just to see if it works. That would at least point to the problem being with Slackware's interaction with the Wolfson card, or the 'use-case' scripts. The official Wolfson download is I think based on the Raspian distribution, so if you are using something else that may produce anomalies. Maybe Ragnar would know something, as he seems to be pretty knowlegeable.

                            • Re: Wolfson Audio Card - no SPDIF out.
                              slackhead

                              Yes Slackware /is/ the oldest surviving distro :-)

                               

                              I have just bought a 32G card so that does leave the 16G card I could do something with, but there isn't any interaction between the distro itself (just a bunch of software anyway) and the sound card; it's all down to the kernel and and the player. I built mplayer from source and I know it works fine on other boxes with the same DAC. It could be something to do with alsa though...

                               

                              No, I really think this is down to the kernel, alsa, the card, or some setting that needs changing in the SPDIF_playback.sh script,

                                • Re: Wolfson Audio Card - no SPDIF out.
                                  tyres2

                                  Dave Wood wrote:

                                   

                                  Yes Slackware /is/ the oldest surviving distro :-)

                                   

                                   

                                  I'm sure I remember that coming on two floppy disks! A boot disk and a RAM disk :-) Seems like cave-man stuff now.

                                   

                                  I've not delved into the 'use-case' scripts. They just worked, so there was no need. I think they are basically setting up Alsa, so that may be where you need to look.

                                    • Re: Wolfson Audio Card - no SPDIF out.
                                      slackhead

                                      Slackware had progressed a bit these days. It's quite up-to-date even though it still uses the old dialog installer and pkgtools. The best thing is no automatic dependency resolution. It's left for the admin to consider what else needs installing for deps.

                                       

                                      Anyway, back to the problem: I've just had a look at my PSU and noticed that it's only rated at 1A. I think that could be the problem. It was one of these 'deals' on amazon where you buy a few accessories along with the Pi. From what I've read it's best to get one rated at 2A. I don't think that I have another to test with at the moment. Need to go through my spares boxes...