Supernait + Airport Express = 1/2 second dropout at 5 seconds into audio stream

Posted by: MattP on 14 November 2008

Hello,
I've got a problem with streaming audio via an airport express (via itunes) to a supernait via an optical cable.
Consistently, at the 5-6 second mark into a stream (song) the audio drops for about a half second then recovers. The rest of the stream plays without interruption until a new stream is created for the next song then it repeats at the same point.
My suspicion at this point is that it is something that the supernait is doing, due to:

1. Occurs when either of my two Airport Express devices when plugged into the supernait via an optical cable (removing AE issue).

2. Occurs when AE is cabled directly to the mac with wireless turned off (removing wireless issues).

3. Occurs on multiple source Macs, both desktop and laptop (removing some issue with the individual source computer.)

4. Streaming via AE to a Yamaha AV amp via same optical config does not have any dropouts. (again, attempting to remove AE issue)

5. When playing to both internal computer, and SN via AE, the internal speaker continues to play the stream whilst the SN/AE drops out and recovers at the same 5-6 second mark.

6. There are no dropouts when directly connecting the mac to the SN via an optical cable – in fact this is how I’ve had it configured for the past year. Its just now I’ve moved the SN further from the computer than the optical cable can reach.

Any ideas? Has anyone else experienced this issue?

Matt
Posted on: 22 November 2008 by james n
Ok - this will isolate whether its a DAC or Network etc etc problem. Try the analogue out of the AE - if you get drops the problem is your streaming system. If you don't then it points to the DAC in the SN and how it handles a temporary clock loss. I take it the SN has no lock light or anything to show (other than audio coming out) that its locked to an incoming data stream.

Cheers

James
Posted on: 22 November 2008 by garyi
For it to be an issue of the supernait everyone would have to experience the same issue.

As this is not the case one has to assume other factors, I have pointed out a main issue earlier in the thread.

If with analogue the supernait works it may still not mean the supernait is the cause of the issue but how the data is outputted from the express.

First things first does anyone experience issues with the earlier 'g' express?
Posted on: 22 November 2008 by james n
quote:
As this is not the case one has to assume other factors, I have pointed out a main issue earlier in the thread.


The original poster found it happened with the AE, but not the mac straight into the SN. His AE into a Yamaha AV receiver doesnt do it either. So it points to the SN ahd how it handles the stream from the AE.

If i take my old print duty AE and stream to it (hardwired to take wirless out of the equation) -

N-Vi occasional drop outs as per r-tee.
Lavry - No drop outs but i see it unlock very briefly at about the same point as i'd hear a drop out on the n-Vi.

I'd agree that it does seem to be an issue with how iTunes buffers the data and how different DAC's handle it. This seems to make the difference as to whether its a problem or not.

James
Posted on: 22 November 2008 by MattP
- James, Playing via the AE analog out is good - no dropouts experienced.

The real problem for us users is that the three devices in the chain (iTunes, AE, SN) are all 'black boxes' so there is no friendly mechanism to monitor or diagnose the process within each one. This works fine until something doesn't work! (I'm excluding the network here, as at least in my case I've discounted it from the potential cause list.)

The fact that the SN dropouts do not seem to occur when streaming from iTunes 7, would indicate that the streaming logic has changed between v7 and v8 (whether in the AE or itunes sw I don't know). The fact that no dropouts are experienced (either itunes version) using a different (yamaha) amp shows that perhaps the internal mechanisms on the amps are different (as expected).

I for one would gladly welcome some technical input from an expert in one of the three 'black boxes' on whats going on. In a naim forum, most likely candidate would be a naim engineer if possible, - someone whom can follow the actuals, rather than relying on our more limited group ability to test, and our rather better ability to speculate!

Me? I've relocated the SN and Mac to within toslink distance again, use AE#1 to Yamaha AV amp (no issue via optical) and AE#2 via analog out..

Matt
Posted on: 22 November 2008 by garyi
James its not that I don't agree with you, but to firmly put the issue in one area it has to happen to everybody agreed?

If every single person using an airport express N into a supernait experiences the same issue then it could be an issue with the SN.

If everyone using an express but a variety of dacs gets even occasional issues then it could be the express, network or itunes.

Similarly if people using say an appletv into a supernait and never have issues, and assuming that the appletv has the same gumph as an express then again its likely to be somethig other than the SN.

Its so specific a problem 8 seconds in that its going to be itunes, I am willing to bet on it, and it certainly appears that rolling back a version is working for some.
Posted on: 22 November 2008 by james n
Well good luck in finding a cure then Matt if you carry on with the AE.

James
Posted on: 22 November 2008 by spacey
ummm after installing v8.0.2.20 of itunes i now get the same tiny blip form the nas and the local HHD in the laptop. so its not the Nas! the only time i dont get it now is when i have the laptop plugged directly into the supernait and is not using any type of network (my laptop has optical out)... so from that i deduct it can only be the AE.
Posted on: 22 November 2008 by james n
r-tee - worth trying the analogue out from the AE - it'll just rule out network etc issues.

Right i'm really going to bugger off this time - good luck guys Smile

James
Posted on: 22 November 2008 by spacey
i have two laptops one with vista the other with xp pro SP3. both do exactly the same thing

how do i disable the WLAN autoconfig in vista?
Posted on: 22 November 2008 by spacey
thanks avole, that would be great if you could.

i dont have any leads for the AE analogue output. what are you using james?
Posted on: 22 November 2008 by james n
I just had an old 3.5mm stereo to two RCA plug lead (heritage unknown but its in my collection of 'could be useful one day' cables') that i tried into my 282 RCA inputs (and opto into the n-Vi and Lavry).

James.

PS - even a basic single mono 3.5mm to RCA would do - at least it would validate the AE analogue out. Anyway my setup is Mac mini straight into the Lavry - i just my AE into my n-Vi and Lavry to see if i could get the same results as you guys.
Posted on: 22 November 2008 by spacey
umm i have worked that out james i just plugged some earphones in and guess what........... no blip. but that does not rule out the digital signal out of the AE. it does mean however the that wireless network(router), nas, laptop and OS system/s work spot on! when i use the optical out from the laptop directly in to SN i dont get the blip either meaning it has to be the AE.
Posted on: 28 November 2008 by js
I'd try to live with it for a bit I'm sure apple will come up with an Itunes fix soon enough. Search 'itunes 8 dropouts' and you'll find it's the issue.
Posted on: 28 November 2008 by Mickyblueyes
quote:
Search itunes 8 dropouts


This will reveal my question My Mac forum thread on the Mac forum, which as yet hasn't born any fruit sadly
Posted on: 28 November 2008 by Mickyblueyes
oops
Posted on: 28 November 2008 by Mickyblueyes
Without wanting to sound thick

How do you;

quote:
so I stopped the WZC service. Instant magic
[/QUOTE]
Posted on: 28 November 2008 by Mickyblueyes
quote:
Originally posted by avole:
On XP it's:

Start>Control Panel>Administrative Tools>Services

Find the Wireless Zero Configuration service, highlight, right click and choose stop.


Oh b@gger thought it was a Mac Fix sorry Frown
Posted on: 30 November 2008 by spacey
quote:
Originally posted by avole:
r-tee,

Quick question I meant to ask earlier: what level of raid are you using?


hello avole, im using raid1. the dropout i get is only one per album and thats about 5 seconds into it. its hardly a dropout either. its more of a split second mute.
Posted on: 01 December 2008 by spacey
just done one other combo. music on NAS played wirelessly from laptop via itunes 8.02.2 but this time no AE. plugged the 3.5mm mini optical jack straigh into the laptops digital out. no dropouts so its 100% an AE issue.
Posted on: 01 December 2008 by Mickyblueyes
quote:
Originally posted by r-tee:
just done one other combo. music on NAS played wirelessly from laptop via itunes 8.02.2 but this time no AE. plugged the 3.5mm mini optical jack straigh into the laptops digital out. no dropouts so its 100% an AE issue.


Or more likely AirTunes software in iTunes v8
Posted on: 01 December 2008 by spacey
yerp. its airtunes/AE both use bonjour so it maybe worth while keeping an iopen for updates Smile
Posted on: 01 December 2008 by Mickyblueyes
I will keep both i'sOpen Big Grin