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Hi guys, I exchanged my Arcam rDac for a new one yesterday. I'm glad to say that the new one works fine from the moment I turn it on, so the previous one was faulty. mpd/alsa/voyage etc was all working fine. Again thanks for the help everyone gave on here. Ben

I'm now 99.9% sure it is a hardware problem, but I will update this thread when I get the new unit at the weekend. If I still have the same problem with the new one, (I really hope I dont!) I will post all the details to alsa-devel.

Thanks for comparing. I don't think either of those entries makes much difference. The bind_to_address should only affect which other computers on the network can connect to it. Admittedly the mixer_type should probably be set to "disabled" or "none" (looking at the manual) but again I don't see that this would cause the issues I am having. As it is, the volume control on the mpd client does nothing at all. Regards Ben

Hi Jarek, I don't have any computers running Windows, so I can only test it on Linux unfortunately. However, the issues I have are identical whether I use Voyage or Ubuntu, and on different hardware. I also wondered about any conflict with USB devices, so a few days ago I disconnected everything (wireless keyboard and media remote control) from my computer, only leaving power, network and the rDac plugged in. It made absolutely no difference. I have now run 3 tests in the last few days with consistent results. Twice I have turned on the system, tried to play music and just got crackles and pops. I have left it alone for 1 hour and then pressed play again. I then get perfect music output. To make sure it was the rDac that needed to warm up, I also tried switching that on from cold, but leaving my computer off. After an hour I switched the computer on and it worked correctly again. The glitches (this is the right word by the way) are not just small glitches over the music. I get no music at all - just the crackle and pop noises. These tests I have done seem to be consistent and conclusive that something inside the rDac needs about 1 hour to warm up. I think I have eliminated every other possibility. I have arranged to swap it for a new rDac next weekend, so I will see if that fixes it. I have also attached the output of the commands you asked for: cat /proc/interrupts lspci -v lsusb lsusb -v I ran these commands twice: first just after turning the system on when it wasn't working, and again after 1 hour when it was working. All the output was identical, except the interrupts which of course change slightly. I have also attached my mpd.conf file, although I think I only changed the audio_output section. The rest is the default from Voyage mpd. Regards Ben

Hi Jarekmor, My alsa_output config is exactly the same as yours, and the output of cat /proc/asound/card1/stream0 is identical apart from the "Momentary freq" I did some more experimenting yesterday and I am now convinced that my rDac is faulty. To test it I turned on the rDac and tested it initially, and it had the low frequency. I left it alone for an hour or two to warm up. When I came back it happily played music at the right frequency. I had not made a single change. I assume that whatever it uses to set the frequency (a quartz crystal?) is fauly and only starts to work correctly when it warms up. Even then the momentary frequency is not perfectly stable. This forum has been a great help to me in figuring this out as I knew my configuration was correct. Looks like a trip back to Richer Sounds for me! Thanks

Hi, I notice a couple of people on here have the Arcam rDac, which I have also just purchased, but I'm having great difficulty getting it to work reliably and I was hoping someone might have some advice. I have it connected to an Acer Revo running Voyage MPD 0.8 via USB (although I have also tried connecting it to my laptop running Ubuntu 11.10 with mpd 0.16.7 built from source with the same results). When I initially try to use it, any attempt to play music through it results in crackles and pops rather than any music. Looking at /proc/asound/card1/stream0 it shows that the momentary frequency is 43944 Hz (0x2b.f198) which is too low. If I try to play a 88.2KHz FLAC file, the momentary frequency is 88612 Hz (0x58.9ccc). Sometimes I get a second of music initially before all the noise, and quickly checking stream0 I can see the momentary frequency dropping from 44100 to 43944. /proc/asound/card1/pcm0p/sub0/hw_params always reports the correct frequency. I have tried changing the order in which I start things up, I have tried changing USB ports, switching the unit on and off, adding different frequency files to my mpd playlist, but all to no avail. Eventually, after much fiddling it generally starts to work, but I cannot reproduce any set of actions that cause it to work. It is almost as if it requires about 30 mins to "warm up" before it will work. From that point on, it performs perfectly. The momentary frequency is correct (although it often fluctuates by 4Hz above and below the 44100Hz mark but I don't hear any problems). It is starting to drive me slowly insane so if anyone has any idea I would be very grateful. Could it be a hardware problem with the rDac rather than software? I noticed that some people have reported almost the opposite issue to mine, where the frequency is too low for the first second, causing a slight glitch. I am assuming they might be related in some way.