Cyrus PreXpdQX - Sonos mains humm

[lbafsaj]

Help, this is driving me mad.

I recently ran my system with main source as Ipod classic with a Onkyo NDS1 dock to send the digital signal into my Cyrus PreXpdQX.

I connected up the Sonos, very easy, via hardwire ethernet, and developed a mains humm. This is only on the Sonos, other analogue sources are OK on my amp.

I use a digital co-ax and have tried an optical cable with no difference. I have setup again using a wireless connection ( as the humm is silent on first switching the system on and only appears after a few minutes of playing music, so I though it could be network interference). Still no improvement.

I have also tried totally disconnecting the sonos ( unplugging) and connected to the digital input on my amp using my DVD player as a transport and still get the humm.

So it seems this issue looks to have been originally caused by the Sonos, but is affecting the DAC ( digital sources only) in my amp.

All my components are connected using good quality mains blocks ( merlin), and I have no loose connections and as I say, i dont get this on any other equipment.

I also have a sonos play 1 in the kitchen and get no humm whatsoever.

So it seems it's casued a problem with my DAC.

Any ideas ?????

 

[The_Lhc]

I'd be extremely surprised if the Sonos has caused a problem with the DAC, it isn't doing anything different from any other digital or analogue source (in fact the analogue outputs are said to be lower power than most sources, so it's unlikely to have overloaded anything). Wiring an ethernet cable to the Sonos isn't going to make any difference either, there's no power running through the ethernet cable.

Clearly as you get the hum with other sources (now) there's a problem in the DAC, have you tried the Onkyo dock again to see if that hums now? How was that connected, co-axial or optical? I'm wondering if you've yanked on the coax plug too hard when you removed the Onkyo and damaged it in some way? Just a guess of course.

 

[skippy]

Dunno whether it's the similar thing, but I've had an issue where a power cable crossed the analogue outs on my Sonos causing a humm.

I just powered it down and re-routed the cables... Worked for me