Ethernet streaming and occasional white noise on Windows

[IanG-UK]

Well, I have some interesting news on the white noise which has plagued me for months.

I run an Apple single source system ( = a nil source system for most of the last few months since I barely use it now knowing I will get perpetual heavy white noise after as little as 15 minutes) and it is essentially what Devialet use themselves and all line of sight. It could not be more compliant. And I can use either AIR wifi or AIR ethernet.

I've always used a couple of PS Audio PPPs as mains regenerators, positioned behind a dividing wall but in reality very close to my 800s.

Anyway, for reasons I won't bore you with, I've started using the kit without the PPPs.

Having tested this continuously over three days, I can report that the white noise is reduced by 80% - 90%. And once it starts (generally only on hi-res tracks) I can flip over to a 16/44.1 track and this generally clears the noise and within seconds I can return to 24/88.2 stuff on a noise free basis.

Whist the end result remains unacceptable, it is quite clearly substantially improved.

My technical knowledge here is minimal, but I venture to suggest that the "contribution" of the PPP comes from either significant SMPSs or high levels of RFI.

Indeed, when I reported this to Devialet they signalled that this would prove very useful information to their engineers which, on the one hand, is encouraging as it may speed up the delivery of a permanent solution but, on the other hand, is worrying in that this path had presumably not been explored by Devialet themselves. After all, without a PPP, Devialet can recreate this fault in their own offices.

Further testing and report later ...

An update.

The large reduction in white noise seemingly brought about by removing the PPPs lasted for 6 days or so, then full white noise reappeared. 

So what conclusion can be drawn?

Well, my Devialets had been turned off entirely before the PPP removal (off, not sleeping) for a few days before I used them. So maybe the white noise is exacerbated by the circuitry being live (whether on or sleeping) for a prolonged period?

Once the noise returned, I thought I would switch my Master and Companion (I have two 250s so both have the full circuitry) and see if the white noise was present. Purely on AIR wifi, with no other inputs.

Result: No white noise straight away; no whiite noise even after leaving the music playing quietly overnight; but after 10 hours of so, white noise reappeared.

If this is indicative, rather than random, it points to white noise only being present in its most significant form after the Devialet has been powered for a long period (on or sleeping) and after the AIR circuitry has been driven (or drivable) for a long period too.

Anyone else able to come to similar conclusions?

I fed back to Devialet Support but the Support area does not give feedback as that is in the engineers' hands and it appears that Devialet policy there is to say nothing until a definite solution is delivered, which is frustrating. I feel like an unrewarded consultant for them.