Any Known Apple AirPlay 2 Sound Quality Issues?

[dodecahedron]

Outside of the fixed 16/44.1 format, are there any known sound quality issues with AirPlay? I know that theoretically, it uses the Apple Lossless Audio Codec which should guarantee a lossless transfer of data (again, assuming a source with 16/44.1 format). But the theoretical world and the practical world don't always agree . Has anybody ever made any measurements to verify the quality of the audio provided by AirPlay?

I currently use AirPlay 2 in my "daily driver" setup. I send my music (all lossless 16/44.1) using AirPlay 2 to an AirPort Express which is connected to my DAC via TOSLINK. I have never experience any sound quality issues myself, other than a small gap in the audio once in a blue moon (I assume due to network issues).

 

[redcloud]

I’m considering the same setup - Airport Express to an RME ADI 2 DAC.

 

[Wes]

any measurements to verify the quality of the audio - like what?

do you think it is losing bits or something?

maybe the downstream analog stage is not great?

 

[voodooless]

There are some test out there: https://kenrockwell.com/apple/airport-express-audio-quality-2014.htm

 

[Jazz]

The Express has a good AKM DAC in it.

 

[dodecahedron]

do you think it is losing bits or something?

I guess I’m wondering if the quality ever gets purposefully degraded (switch to a compressed codec, lower bitrate) when there is any network/latency issues.

 

[dodecahedron]

There are some test out there: https://kenrockwell.com/apple/airport-express-audio-quality-2014.htm

Thank you! I had no idea that such detailed data existed for such an old and outdated device

 

[Frank Dernie]

Thank you! I had no idea that such detailed data existed for such an old and outdated device

Old for a computer device which will be deliberately obsoleted even though it works perfectly, so you have to buy a new device which is no better
Almost all my hifi is older than that.

 

[Wes]

I guess I’m wondering if the quality ever gets purposefully degraded (switch to a compressed codec, lower bitrate) when there is any network/latency issues.

Interesting thought.

My guess is no, since my Apple TV (the old one with an optical out to a DAC) will stream video just fine.

 

[oryan_dunn]

Yes, the Airport Express A1392 with firmware 7.8.x (7.8.1 being the latest) and Airplay 2 has audio quality issues crackling/static. It seems solo piano really highlights the issue. With rock/pop/etc. you have to listen pretty carefully to hear it. This issue is present on both the analog and toslink outputs.

These recordings were made using AE->Schiit Magni 2 uber (for analog volume control using the pre-outs) -> line in on my motherboard. I hope you're able to download these from OneDrive.
I had issues with the AE overloading the input to my motherboard, so once I fixed that, these recordings are what I hear. First is the song played via 7.6.9
https://1drv.ms/u/s!Auh_3Af5efZQoYt8bmjTjuahYyCHmw?e=ky5RyK

And the second is the same song played via 7.8.1
https://1drv.ms/u/s!Auh_3Af5efZQoYt9Imlq23MeBW-5RA?e=zkp6h3

This song is played via Apple Music on an iPad Pro 10.5 with iPadOS 14.4.1 and iPad's digital volume set to 100%.
Direct link to the song if you have Apple Music

Here is the clip from iTunes 12.11.0.26 on Windows 10, far less crackling, but it's still there
https://1drv.ms/u/s!Auh_3Af5efZQoYt-PO9X5rMWf-1IIA?e=67UJyn

Inspecting these recordings in Audacity, I don't see the tell-tale signs of clipping, even in the 7.8.1 release, but you can definitely hear static. If it were clipping, I'd have expected the digital volume control to fix it, but even dropping it very low, and turning up my headphone amp, I still hear the static.

Reverting back to firmware 7.6.9 and Airplay 1, audio is crystal clear. With this downgrade, you lose Airplay 2 for synced multi-room playback, and it seems Airplay 1 is much more prone to dropping the stream if you pause the music for a minute or so, and I have to turn the the volume every time I connect with Airplay 1 since it never remembers that I have the digital volume at 100%. It'd be really great if Apple released a firmware fix for this. Since I doubt they'll do that (7.8.1 was released in 2019 for a discontinued product), hopefully that Belkin adapter will perform better than this.

 

[Alexanderc]

Hmmmm… I just today bought a used AE 1392. Hadn’t heard about this issue. I guess I’ll hope it comes with the old firmware and I just won’t upgrade.

 

[mkawa]

Ap2 almost always uses alac. I have noticed bugs in device implementations though. Ap1 is much more consistent and with Big Sur almost always uses alac as well

 

[oryan_dunn]

Hmmmm… I just today bought a used AE 1392. Hadn’t heard about this issue. I guess I’ll hope it comes with the old firmware and I just won’t upgrade.

Fortunately, Apple makes it very easy to change firmware versions with the Airport Express utility. You can freely bounce back and forth and do your own testing.

 

[mononoaware]

Hi everyone,

Just to report my experience with using the Mini-Toslink output on the A1392 Airport Express.
A while ago I bought the A1392 second hand to use as a AirPlay receiver connected to a DAC and the results were pretty terrible.
Using it connected to the SMSL SU-8 V2 DAC via Toslink resulted in audio which was constantly interrupted and with glitchy artefacts.
Most likely extremely high amounts of jitter, which caused the DAC to have a tough time keeping the signal.
After extensive searching online, many had the same experience and it seems that Apple had "broken" the Optical (Mini-Toslink) output of the A1392 with firmware updates.
I cannot recall the firmware number exactly, but a select few past firmware options had flawless Optical output.

I hoped the A1392 could be rolled back to this “golden” firmware, but it had already been updated to the latest (which supports AirPlay 2) and among the "roll-back" options the old firmware without the broken Optical output was no longer an option.
At this point I tried all available roll-back options and they all had the same issue with the digital output.

On the latest firmware the analog 3.5mm output (using the A1392's built-in DAC) works absolutely fine.
(Apparently there were security updates in the latest AirPlay 2 supporting firmware, so I just left it on that firmware since all of the available ones are broken with Optical anyway)

I have been using an Apple TV 3 as a AirPlay receiver through Optical (Toslink) long before trying the A1392 and have never had any issues with the SMSL SU-8 V2 DAC to this day (even after a recent "auto" firmware update).

In those cases where people are saying "it works" my guess is your DAC is more tolerant to jitter, but when there are "gaps" or "artefacts" in your audio it is just your DAC having a tough time with the poor digital output of the A1392.

I have never experience any sound quality issues myself, other than a small gap in the audio once in a blue moon (I assume due to network issues).

Those are most likely not network issues, but issues with the digital output of the A1392.
Try using the 3.5mm analog output of the A1392 and see if you experience the same issue.

 

[mononoaware]

Reverting back to firmware 7.6.9 and Airplay 1, audio is crystal clear. With this downgrade, you lose Airplay 2 for synced multi-room playback, and it seems Airplay 1 is much more prone to dropping the stream if you pause the music for a minute or so,

I tried all of the available firmware roll-back options, all had the same issue with optical output (mini-to slink) and it was very bad to the point of being literally broken, audio constantly interrupted and with artefacts.

and I have to turn the the volume every time I connect with Airplay 1 since it never remembers that I have the digital volume at 100%. It'd be really great if Apple released a firmware fix for this. Since I doubt they'll do that (7.8.1 was released in 2019 for a discontinued product), hopefully that Belkin adapter will perform better than this.

Funny I have the opposite with the latest update for the Apple TV 3, each time I connect to it via AirPlay it defaults to "Max volume" instead of remembering volume like it did previously.

Yes hopefully A1392 Optical output can be fixed with firmware, but I think Apple is aware most consumers just use the 3.5mm analog output so they prioritised AirPlay 2 and security features etc.

 

[oryan_dunn]

I tried all of the available firmware roll-back options, all had the same issue with optical output (mini-to slink) and it was very bad to the point of being literally broken, audio constantly interrupted and with artefacts.



Funny I have the opposite with the latest update for the Apple TV 3, each time I connect to it via AirPlay it defaults to "Max volume" instead of remembering volume like it did previously.

Yes hopefully A1392 Optical output can be fixed with firmware, but I think Apple is aware most consumers just use the 3.5mm analog output so they prioritised AirPlay 2 and security features etc.

For me, both toslink and analog work flawless on 7.6.x firmware and both have those crackles/static on 7.8.x, so the issue my files above show there are issues with the analog output as well. That crackling is much more noticeable on some music via headphones.

With a company the size of Apple, you'd expect them to have a rigorous test setup for software releases that would catch these things. It's a real shame, since with good firmware, it's a great device; frustrating that they're so close.

On the latest firmware the analog 3.5mm output (using the A1392's built-in DAC) works absolutely fine.

Those are most likely not network issues, but issues with the digital output of the A1392.
Try using the 3.5mm analog output of the A1392 and see if you experience the same issue.

Try using the analog output on 7.8.x with some solo piano music and listen via headphones. I'm curious if playback would be crackle free for you (if possible, try with the song I linked above).

 

[Alexanderc]

Disappointed to about these issues. I have the option to use either mini toslink or 3.5mm so I expect mine will at least be useable. I don’t really expect to hear any difference compared to my receiver’s dac, I just don’t like the idea of doing multiple digital-analog conversions. I’ll report back when mine arrives.

 

[tmtomh]

Airplay 1 and 2 have no audio issues in the sense that they use reliable ALAC (redbook sample rate and bit depth) and never employ lossy compression.

The audio issues Airplay does have, as noted above, mainly involve hardware and/or firmware that makes the optical-out on some units unreliable because it has very high jitter and poor clocking. Some external DACs can't lock onto the signal, and others can but manifest the aforementioned ticks, clicks, and or staticky sounds. My understanding is that some generations of the Airport Express have this problem baked in regardless of firmware version, but if that's incorrect I'm happy to hear that!

Years ago when I used an AE, I experienced minor, occasional ticks or clicks even when using the AE's analogue output. That is clearly something to do with the wi-fi transmission from the Mac to the AE, and I have no idea if it was the Mac, my local network, or the AE. I suspect it was more likely the Mac or the network, because as far as I know the AE units have no systemic issue with audible problems from the wireless transmission itself - I think the AEs are the source of problems only when using the optical out. Happy to be corrected if I am mistaken.

 

[oryan_dunn]

I should note, I have two A1392 manufactured years apart (June 2014 and September 2015), and both units exhibit the same behavior. In my testing, it didn't matter if I used WiFi or ethernet, the results were the same.

Also, as noted above, the source did make a difference. There was less crackling when I Airplayed from iTunes on my Windows machine than when I did it from my iphone or ipad. In addition to Apple Music on my iPhone, I used Spotify as well, with the same results.

Airplay 1 and 2 have no audio issues in the sense that they use reliable ALAC (redbook sample rate and bit depth) and never employ lossy compression.

Yes, I would agree the Airplay protocol is likely not the issue here, just firmware bugs with the Airport Express.

 

[dodecahedron]

Thanks @oryan_dunn for reporting the solution to the problem you've been having with the Airport Express A1392. I ran into the exact same issue myself!

For weeks now, I had noticed these popping/crackling sounds and they were slowly driving me crazy. I could prove to myself that they were not coming from my amp, so I simply assumed that the issue was with my ageing DAC (and I never even considered it could be an issue with the Airport Express). So I bought a new DAC a few days ago and I was shocked when the same crackling sounds were still present.

After some research, I also downgraded my firmware from 7.8.1 to 7.6.8 and now the issue seem to be gone. However, I'm finding myself using a direct USB connection to my laptop more often since this issue. I guess I don't trust AirPlay as much as I used to anymore. On the positive side, I finally upgraded my DAC .

I was planning to write a post about my experience on the weekend, but you beat me to it! Hopefully this discussion can help other people having the same issue.