[LostArk]

For the past 7+ years I have used an Airport Express and AirPlay (formerly AirTunes) connected to my receiver via S/PDIF. My first receiver was an el cheapo Sony 5.1 home theater in-a-box, and (ironically) it received the Airplay signal without issue. 3 years ago I upgraded my speakers to a nice stereo setup, and upgraded my receiver to match; a Harman HK-3490. All was well except for one minor problem: when skipping (or pausing) a song manually, more often than not my speakers would pop. Sometimes it was a faint pop, but sometimes it was startlingly loud, enough to concern me with the possibility my speakers might be damaged. Given there were no other problems, and that I don't often skip songs, I put up with this behavior until recently (note, however, that I did narrow down the problem as either a fault in the AirPlay software or the receiver's DAC). Last week I ordered a Yamaha RX-V475, thinking that built-in AirPlay compatibility would resolve the pop when changing songs. I was right - though unfortunately I am now contending with a new and far worse scourge: clicks and pops during playback. 
 
These three threads on the Apple forum confirm I am not the only one with this issue:
 
Thread one, thread two, thread three.
 
In my efforts to eliminate the problem, I have again narrowed down the fault to either a) AirPlay software, b) the receiver's DAC, or c) EMI
 
I have narrowed it down to these possibilities using the following methods. Please let me know if there is something I haven't thought of:
 
I.    Verified it is not a speaker issue as the clicks and pops are present when listening through the receiver’s headphone jack as well.
 
II.    Verified it is not a amplifier issue as output is clean from other digital sources, such as PS3. This makes me think it's not the receiver's DAC.
 
III.     Verified it is not a source issue, see above. 
 
IV.    Clean output at all eliminates grounding issues.
 
VI.    Clicks and pops absent when streaming AirPlay to the receiver: AirPort Express -> S/PDIF -> receiver. This makes me think it's not AirPlay's fault.
 
The fact that I can get clean output under all circumstances except when the receiver is receiving data through a copper (ethernet) connection really makes me think it might actually be EMI! I'm not sure what to do, since the receiver has to be plugged into my router (AirPort Extreme) to work.
 
Suffice it to say, this is really, really madness-inducingly frustrating.
 
So, where should I go from here? Why on God's Earth can't I just get a nice, clean AirPlay signal without insanity-inducing niggles? 

 

[mark2410]

errr guessing but emi or somehow the airplay transmission is being corrupted but that shouldnt be possible.  firmwares all updated?
 
sorry to not be more help but ive never had any issues with it.

 

[Roseval]

The links in the Apple forum points to problems with the Airplay firmware but they are a bit dated
As mark2410 suggested, update the firmware (receiver, any other component using Airplay)
 
The Yamaha RX-V475 is also DLNA enabled.
If you have a DLNA server (PC, NAS) try this. If the problem disappears it is not a network problem.
Internet radio is another option.