View Full Version : Squeezebox 3 problem with s/pdif interface

2008-12-25, 12:25
I've recently bought a Cambridge Audio DACMagic to use as external DAC for my Squeezebox 3. I've connected it through a proper copper cable since the person who sold the DACMAgic to me told it was better than a Toslink.

The thing is while listening I get some micro-interruptions of the audio, once every 5 minutes average, but randomly. It's about 1/10 th of second interruption, enough to be annoying. The DACMagic has front leds showing the presence of the signal and the related sampling frequence. Indeed during the interruption periods the led goes off.
This seems to indicate there is temporarily and for a short period no signal on the s/pdif interface and is the main reason for which I think the problem is on the SB3 side, but I'm not so sure it is the Squeezebox, or the DACMagic.
On the other hand, I connected my earphones to the SB3 and tried to understand what happend when the microinterruption came. The audio signal on the earphone is fine, even during the interruption, so the internal DAC of the SB3 has no problem.

I've done some things, but all useless:

1. I've tried another mains plug for the SB3 and the DACMagic. No result
2. I've swapped the s/pdif cable with another one. No result
3. I've upgraded to the last beta version of squeezecenter, but no result
4. I've spry-cleaned the s/pdif connector of the SB3, thinking that since it had been idle for 2 years it might have been oxidated. No result

The system I'm using is:
- one SB3 bought in april 2006 connected through Wireless LAN to a wireless router. The speed verification goes up to 5 mbps without problems.
- Squeezecenter, last version, running on Vista
- Cambridge Audio DACMagic, brand new
- s/pdif electrical cable from Cambridge Audio, normal grade

I listen mainly to FLAC music ripped from CD, so 44,1 as sampling rate.
The problem appears both on FLAC and on MP3.

Is there anything else I should try to make this work before I go back to the shop with the DACMagic?

Thank you in advance to all and Merry Christmas.

2008-12-25, 13:11
Couple of things worth trying:

* Hook up something other than the SB to the DAC, for example a CD player, using the same cable.
* Get a cheap TOSlink cable to see if it works better with that.
* Someone with a similar problem recently said that using a decent quality video cable instead of the spdif coax worked well.

2008-12-25, 13:25
radish wrote:
> * Someone with a similar problem recently said that using a decent
> quality video cable instead of the spdif coax worked well.

Actually, a quality composite video cable is exactly what the S/Pdif
format specifies. 75 ohm coax.

Ignoring, of course that there are no 75 ohm RCA connectors in the universe.

Pat Farrell

2008-12-26, 13:02
thanks for the suggestions.
I will buy a toslink cable tomorrow.
In the meantime I've found at home a 75ohm video cable of no great quality. I tried it anyway and it did not sort the problem out.

The amazing thing happened yesterday evening and also this evening. From about 20.30 on, the defect disappeared. It came back this morning and now is gone again. I cannot believe it.

The equipment has been on and running for all of the day showing the defect many times, and now (21.00) is gone.

Maybe something to do with power supply and noise in my electricity newtwork? otherwise I have no clue on what is happening.
Any help will be appreciated.


2008-12-26, 21:54
Does the DAC have a dejitter circuit? If it does can it be shut off?

I'd try a different DAC.

2009-01-04, 06:35
thank you to all.
Apologies for not having given a feedback to you all, but I've been out of home for a while and I am back now.
I bought a decent optical cable, connected the SB3 through it and the problem seems to be disappeared. It probably has to do with something in my electrical cabling. The multi-plug socket I am using is probably not of the best quality and shall have to be replaced. Anybody have a suggestion for a decently priced solution? (not more than euro 50)
The current setup is for a simnple multi-plug (one main electrical switch, plus one switch per plug) powering the DVD-player, the SB3, the DAC and the integrated amplifier. On another plug I have a Plasma widescreen, an IOmega HDplayer and a DVB-T external box.
I do not have other mains plugs in the near proximity, so it shall have to be a multi-plug solution. In the stores near where I live (Milan, Italy) you can find what I would call "fancy multi-plug sockets" from Belkin or similar. Will any of these be a viable option?