Airplay 2 Cast Beta - Testing experiences

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Please use this thread only to discuss your personal experience with the testing of the Airplay 2 Cast feature and the beta firmware you requested. This thread should not replace submitting tickets as that route provides WiiM support with the necessary device and app logs to diagnose and hopefully fix any issues.

From what WiiM have already posted:

“For those testing please see the tutorials below.
We appreciate your ongoing participation as a Beta tester. To use AirPlay 2 Cast, please update your WiiM Home App to the newest version. For iOS users, please update to version 2.5.5, and for Android users, please update to version 2.5.4.

Firmware 4.8.525058 only includes the AirPlay 2 Cast feature.

If you encounter any issues during the update process or while using this function, please do not hesitate to contact us. Your feedback is invaluable to us.

Thank you for your continued support and contribution to our Beta testing program!”
 
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And there is the AirPlay 2 scenario described when bit-perfect is achieved, which was working for me before but it doesn't work with WiiMs any longer.
Hi Onlyoneme,

Our engineers have conducted tests to verify the bit-perfect feature when using AirPlay Cast. The test setup is as follows:

1. WiiM Pro #1 - Receives a 44.1k/16-bit ALAC test signal from the DLNA server, then sends it to WiiM Pro #2 via AirPlay Cast.
2. WiiM Pro #2 - Receives the test signal and saves it for comparison.

We compared the received PCM with the original PCM decoded from the ALAC test signal and found them to be exactly the same. This result was consistent across several test signals.

If possible, please share your test PCM, and we would like to cross-check it in our lab. Thank you for your support!
 
Hi Onlyoneme,

Our engineers have conducted tests to verify the bit-perfect feature when using AirPlay Cast. The test setup is as follows:

1. WiiM Pro #1 - Receives a 44.1k/16-bit ALAC test signal from the DLNA server, then sends it to WiiM Pro #2 via AirPlay Cast.
2. WiiM Pro #2 - Receives the test signal and saves it for comparison.

We compared the received PCM with the original PCM decoded from the ALAC test signal and found them to be exactly the same. This result was consistent across several test signals.

If possible, please share your test PCM, and we would like to cross-check it in our lab. Thank you for your support!

I've attached one of the test files I've used, with 44.1/16 resolution.

My scenarios were as below:

1. WiiM Pro fed with the file over WiiM Home app, then stream sent to WiiM Pro Plus via AirPlay cast. Content captured over toslink output on the Pro Plus using spdif-usb interface. Result - not bit perfect.
2. WiiM Pro fed with the file over LMS and LMS DLNA bridge, then stream sent to WiiM Pro Plus via AirPlay cast. Content captured over toslink output on the Pro Plus using spdif-usb interface. Result - not bit perfect.
3. WiiM Pro fed with the file over LMS and LMS AirPlay bridge. Content captured over toslink output on the Pro using spdif-usb interface. Result - not bit perfect.
4. WiiM Pro fed with the file over LMS and LMS DLNA bridge. Content captured over toslink on the Pro output using spdif-usb interface. Result - bit perfect.
5. WiiM Pro Plus fed with the file over LMS and LMS DLNA bridge. Content captured over toslink on the Pro Plus output using spdif-usb interface. Result - bit perfect.


4. and 5. are successful also when WiiM Home app is used.
 

Attachments

  • 441_16_adi2pro_bittest 4s.wav
    694.2 KB
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Hi Onlyoneme,

Thank you for your reply and the test file.

It appears that you indeed achieved bit-perfect output in some of your use cases. This leads me to believe that AirPlay Cast does provide bit-perfect results in these instances.

For use cases 1, 2, and 3, where the bit-perfect process was disrupted, could you please provide more details? Specifically, we need to know if your test device is Android or iOS, and whether you sent the same '.wav' file from the WiiM Home App to the WiiM Pro. This information will help us identify the root cause.

Thank you once again for your assistance!
 
Hi Onlyoneme,

Thank you for your reply and the test file.

It appears that you indeed achieved bit-perfect output in some of your use cases. This leads me to believe that AirPlay Cast does provide bit-perfect results in these instances.

For use cases 1, 2, and 3, where the bit-perfect process was disrupted, could you please provide more details? Specifically, we need to know if your test device is Android or iOS, and whether you sent the same '.wav' file from the WiiM Home App to the WiiM Pro. This information will help us identify the root cause.

Thank you once again for your assistance!
Hi @WiiM Support !

These bit-perfect cases are ones where AirPlay was not involved at all. I provided them as a reference to show that feeding with the source material and capturing it on the target device, both work correctly. All my AirPlay related cases have failed the bit-perfect test.

A test file was the same all the time. I've used WiiM Home app for iOS, Android and Windows, it didn't make a difference here.
 
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Hi @WiiM Support !

These bit-perfect cases are ones where AirPlay was not involved at all. I provided them as a reference to show that feeding with the source material and capturing it on the target device, both work correctly. All my AirPlay related cases have failed the bit-perfect test.

A test file was the same all the time. I've used WiiM Home app for iOS, Android and Windows, it didn't make a difference here.
Hi Onlyoneme,

Our engineers conducted a test using your signal files, and the results differ from yours but align with our expectations. Here's a detailed breakdown:

We used the WiiM Home App to stream test wave files to WiiM Pro #1.
WiiM Pro #1 then streamed these files to WiiM Pro #2 via AirPlay Cast.
We saved the PCM results on both WiiM Pro #1 (named file 1) before sending via AirPlay Cast, and on WiiM Pro #2 after AirPlay receiving and decoding (named files 2 and 3). On WiiM Pro #2, we conducted tests with skew processing both enabled and disabled, resulting in two different files.

File 1 and file 3 are identical, confirming bit-perfect transmission when skew processing is disabled. File 1 and file 2 differ, but not as significantly as in your figures. This difference is attributed to the skew process.

I attached the three screenshots for your reference (Sorry, not very clear).

File 1
file1.jpg
File 2
file2.jpg
File 3
file3.jpg
 
Hi Onlyoneme,

Our engineers conducted a test using your signal files, and the results differ from yours but align with our expectations. Here's a detailed breakdown:

We used the WiiM Home App to stream test wave files to WiiM Pro #1.
WiiM Pro #1 then streamed these files to WiiM Pro #2 via AirPlay Cast.
We saved the PCM results on both WiiM Pro #1 (named file 1) before sending via AirPlay Cast, and on WiiM Pro #2 after AirPlay receiving and decoding (named files 2 and 3). On WiiM Pro #2, we conducted tests with skew processing both enabled and disabled, resulting in two different files.

File 1 and file 3 are identical, confirming bit-perfect transmission when skew processing is disabled. File 1 and file 2 differ, but not as significantly as in your figures. This difference is attributed to the skew process.

I attached the three screenshots for your reference (Sorry, not very clear).

File 1
View attachment 1945
File 2
View attachment 1944
File 3
View attachment 1943


Hi @WiiM Support !

I must admit that your waveforms, those identified as bit-perfect, look weird a bit for me. Was it captured in the digital domain?

That's a bit better visualization of the waveform I got with AirPlay:

1691757869353.png

It looks very similar to the one you got with file 2 with skew processing enabled.

Below is the content captured without AirPlay, which is exactly the same as the source:

1691758115746.png


I guess that skew processing is enabled by default now thus getting bit-perfect results via AirPlay is no longer possible. Is that right?
 
Or maybe these waveforms were captured with some processing involved? Mine have EQ disabled, 100% vol, etc.
That could explain a slightly deformed shape for your 1 and 3 files.
 
Hi @WiiM Support !

I must admit that your waveforms, those identified as bit-perfect, look weird a bit for me. Was it captured in the digital domain?

That's a bit better visualization of the waveform I got with AirPlay:

View attachment 1946

It looks very similar to the one you got with file 2 with skew processing enabled.

Below is the content captured without AirPlay, which is exactly the same as the source:

View attachment 1947


I guess that skew processing is enabled by default now thus getting bit-perfect results via AirPlay is no longer possible. Is that right?
Hi Onlyoneme,

The skew processing is a necessary feature enabled by default in the AirPlay receiver. It's used to compensate for the clock discrepancy between the sender and receiver, specifically allowing the receiver to align with the sender's clock.

I suspect that the waveforms you're seeing are the same, but they may be visualized on a different scale from what you have. I'll confirm this with our engineering team.
 
Thx for the explanation, @WiiM Support .

I guess I can summarize it now: the AirPlay transmission from / to the WiiM is not bit-perfect regardless of the resolution used, although it was partially possible in the past. There is no way to make it bit-perfect due to the skew processing which is mandatory.
 
Hi,
Just installed the latest public version including Airplay Cast. Interesting feature.
But just a question, is it possible to select several output?
As an exemple COAX + Airplay could be a nice combo.
(We could even consider Coax + Airplay + Bluetooth for a crazy multiroom setup)
 
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Hi,
Just installed the latest public version including Airplay Cast. Interesting feature.
But just a question, is it possible to select several output?
As an exemple COAX + Airplay could be a nice combo.
(We could even consider Coax + Airplay + Bluetooth for a crazy multiroom setup)
Hi Grebg,

Regrettably, this isn't feasible at the moment. Rest assured, we'll take note of your suggestion and explore the possibility of implementing it in the future. Your input is greatly appreciated – thank you!
 
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