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Advice on Sonos into Cambridge CXA / CXN issue needed


Active Member

Hoping you can help with a really annoying problem.

I have a Sonos going into a Cambridge Audio CXN which is connected to a Cambridge CXA80. When Sonos is set in 'Variable' mode (which allows me to control the music from the Sonos App) I have to turn the volume to 100% (full) on app and then use the amp to control the actual listening volume level. The whole idea of course is you can so it straight from the app rather than using the CA remote or walking across room to do it. Its nothing to do with the amp inputs as tried other devices through them and all work fine - same goes for the CXN. Also same happens if I just connect the Sonos straight to the amp with the CXN off and not connected so not that either. Additionally the problem was the same whether using digital (toslink or spdif cables) or analogue (RCA and XLRs)

I called Sonos who did a diognostic of the device and said it has no fault. They then said the issue must be the line level strength required by the amplifier and therefore nothing to do with their device. They suggested there might be some device 'out there a bit like a phono amp' that could boost the Sonos strength? I have no reason to doubt them but they didn't sound 100% sure if I'm honest.

So I also asked Cambridge Audio who said "The CXN and CXA only require a 'Line Level' signal which the Sonos Connect should produce. You are able to connect a phono stage but this would be to the CXA only as the CXN does not have any analogue inputs. This is usually used for items such as turntables that require extra amplification."

So that's where I am. Is there nothing to be done? Is it the amp? Is it the Sonos? Is something faulty or is this just normal? I have no idea!


Distinguished Member
Just out of curiosity, if you have the Cambridge CXN, then why do you need the Sonos? I'm sure there is a Smart Device APP for the Cambridge if that is the issue. And the CXN should be a far better Streaming Device than the Sonos.

Also, do you have the option of using Fixed or Variable on the Sonos, and have you tried Fixed?

And which Sonos device are you using?

The Sonos:Connect has an on-board Volume Dial, if you adjust that does that effect the volume of the output?

That is, if the manual volume on the Front of the Sonos is not set to full, then perhaps it is limiting the range of Volume that can be controlled by the Sonos App. For example, if the front panel Volume Control is set to 50%, then perhaps the range of the App volume is only from 0% up to 50%. If you raise the front panel Volume up to 70%, then the App range is from 0% to 70%, and so on.

I'm not saying the above is the problem, I'm only saying that it is one possibility.

However, there absolutely is a Control App for Smart Devices from Cambridge (Cambridge Connect) - (@ 4:11)

They (Cambridge) don't have a video specifically for the current Control App, but here is there video for the previous version -

The Cambridge CXN has 24b/384k DACs.

The specs on the Sonos are not clear, but they appear to be limit to CD Quality or just a bit above. Though speculation, I would guess the Sonos tops out at 24b/48k.

Again, if you have the considerably expensive high performance Cambridge CXN, I really don't see any point in the Sonos, unless perhaps the Sonos were in a different room, but that does not seem to be the case.



Active Member
Hi Steve

All very valid points and thanks for such a considered bit of feedback.

I work in live music and the Sonos is very much a work horse for me. I need it for the bands and venues I work with and promote. The fields I work in (roots, folk, jazz mainly) means I can source often obscure material very quickly through Sonos. Its interface is second to none and it allows me very quickly to move through various platforms from Tidal to Deezer to Spotify. I'm familiar with it and in terms of SQ once it goes through the CXN its pretty impressive. The CXN is great as well of course but a little more clunky - certainly I'm finding the control app no where near as easy to use although of course familiarity over time may change that view.

The Sonos works absolutely fine in fixed mode - although of course that means I can't then use the volume slider on the Sonos app (or Spotify one if synced) - and with the volume required to be at 100% in 'Variable' it basically just replicates that situation.

Not sure on the Sonos res - they claim its around CD level I think and certainly not hi res but running through CXN seems to really work. Far better than I expected so have no idea what its DACS are doing to the SQ

Good thinking on the volume control on the Sonos itself (is that what you mean - the button with '+' and '-' on it?). Alas though all its done put the volume up to max on the app which I need to do anyway if I'm to hear anything at all

So bit stuck. Back to my actual question I was just wondering if this is a fault with the Sonos as surely the whole point of the variable is that it can do exactly what i want it to do? And I can't quite believe Sonos would create a device whose raison d'etre was to connect seamlessly to mainstream seperate hifi and then not actually achieve that - particularly given how long its now been around for and how mainstream and accessible Cambridge Audio are. Just a bit stumped as not sure whether to just accept the state of things or whether theres something wrong with it....


Active Member
That's a really good point Steve and if honest not entirely sure myself. Staff at Richer Sounds mentioned the 2 high end DACS / upsampling in CXN would really improve the SQ so have run it through there first as CXA80 only has one I believe....but happy to be corrected on this one if that is actually the wrong route to take.

Quick update - posted this on Sonos Community Forum and they just seem to be saying its just how the system works when in variable and your choice is either to have Sonos App at 100% volume or Amp at 100% (risky if more than one external input!) or have both at 50% and see how that works. I'll try the latter today but suspect will be going Fixed with it now. So sounds like no fault unless the Sonos Community is wrong - its just a bit more clunky than I expected (perhaps unfairly on my part)


Well-known Member
As touched on above, put cxn to one input, sonos to a different line in.

You'd normally set amp to a little higher than your normally listen volume and then use your app to control volume if using sonos as preamp

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