The first google that comes up when I search “dwc3” is this kernel issue page.
Not sure if its related? I can’t see a date on the page to see if its old or new
If you get a spare moment, can you do similar test image for RPi4, that maybe fixes the static/FM radio sound? And I can try.
At least I know auto sample rate switching works fine with RPi4 with your latest kernel.
It is already practically same as the -2 test image.
You mean the existing naa-423-raspberrypi4 image is already like the -2 ramfs test image?
i.e. non real-time kernel ?
Yes, there has been no realtime kernel for RPi4 for a while. It is a regular low latency one.
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Just testing RPi4 again.
When track sample rate changes, the 1st second is good and clear sound quality.
After 1 second, it then goes into that ‘bad FM radio station’ quality.
So the fact that its good for 1 second gives hope it is fixable 
But I fully understand finding the precise cause is tricky
And then later in my playlist above, it comes good again, seemingly randomly.
So it doesn’t stay broken for the entire playlist. It’s hard to find a pattern.
I think trying to fix UP Gateway UAC2 input will be too hard if it is dwc3 issue.
But I think RPi4 UAC2 input more likely fixable (just don’t ask me how 
)
And with RPi4, the fact that when you get this static noise with sample rate change , if you pause the track, wait a few seconds and press play to resume the same track, it fixes the issue. The track resumes perfectly fine. Until the next track which changes sample rate - then it is 50/50 chance what you will get when next track begins
So its not completely broken.
Hopefully that gives some hints what it could be.
Sorry interrupt the discussion… the RPi officially released PoE+ HAT recently but the NAA OS only has the old PoE HAT overlay. @jussi_laako would you help us add the PoE+ function into the NAA OS’ kernel? RPi really needs the fan spinning 
(high temperature will degrade the SQ).
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Hi @Chunhao_Lee , are you able to try this playlist below , playing through your RPi4 NAA, output to another NAA ?
Play a few seconds of each track then press next track. Running through playlist. Each track changes sample rate.
Any issues for you?
Playing Atmos won’t reveal any issue because it is all 44.1kHz on Apple Music
Will do but need to solve over temperature issue first 
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HQPlayer OS / NAA OS has the official RPi kernel, so once the support finds it’s way there, it will eventually propagate to my OS builds too.
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Noted , over heating is indeed a major problem ! the major-est
If this POE+ will take a while to reach NAA OS could you power your RPi4 old fashioned way to test this playlist (power over USB using hub connected to Apple USB adapter)
Only if you get a spare minute
So far since last year I am the only person reporting issues with NAA UAC2 input
I cant find anyone to try playing my playlist and to reproduce 
Note the auto sample rate switching works fine. The issue is sound quality, so need to listen 
.
Somebody else above tested and said it worked fine because DAC sample rate was changing on DAC display but that’s not the issue. Issue is what comes out of DAC
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I wonder of its USB-C otg port is dwc2 or dwc3 
For UAC2 NAA input
I suspect in worst case it is just OTG (USB host with inverse connector) and no device mode. In best case it is just another DWC3 IP block. Sorry, I’m a little pessimistic, I’ve been disappointed so many times already.
Those dual-role USB controllers are mainly designed for mobile devices, phones, tablets and such. A bit like Lightning. Where you need to be able to be both device (connection to computer) and host (connection to camera or USB headset). But that market is just not something Intel is strong at. The Atom on original UP Board (aka Gateway system) was designed for mobile (tablet) market.
Many ARM SoC’s are much better on this front, because they are commonly designed to be connected to a PC/Mac through USB.
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Based on the product description of the new Up^2 6000, OTG is Atom CPU only. I think the new Up 4000 might be the same.
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Yes, I think it is likely Atom only. IIRC, for example E3950 has it (I have a E3950 SoM with type-C USB that has dual-role). It is likely that Pentium and Celeron branded chips don’t have it, although those still have Atom-style CPU cores.
Pay attention for example to what is said as “Vertical segment” for each chip:
The old UP Gateway has a Mobile segment chip.
I have a new Up 4000 with E3950 coming. I don’t have a particular interest on the Pentium/Celeron branded models.
I already have fitlet2 with E3950, but it is not really designed for USB device functionality in mind. For the functionality to work, it also needs matching board and associated component design, plus BIOS support. Which means the board manufacturer needs to design and test this. Which is probably not their priority #1 thing.
And I’m pretty hesitant to become a hardware vendor…
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Hmm I wonder what “Starting from Linux 5.18, UAC2 Audio gadget code is completed” means?
Hello guys, I moved here from audiophilestyle, I see in this thread just what I need is being discussed. Hope you can help me.
I read this topic, but physically I don’t have time to read everything, so I’m sorry if the questions are stupid.
As the respected Jussi told me, HQPE can receive a signal not only from RME ADI-2 or Mini DSP, but from any connected to the server or NAA. I need to try to build a system that will receive a stream via UPnP for high quality, but at the same time I would like to still be able to watch youtube and movies, the second input in terms of sound quality is no longer so important, but when transmitting via UPnP from Android devices through the same AirMusic has a big delay so it’s impossible to watch youtube and movies.
The task is to implement one more input to HQPE, for starters, simply through a line input on the motherboard. Then, after checking how the system will behave in terms of delay, I will think about entering via SPDIF.
I’m trying to figure it out, but I have a few questions:
-
I realized that I need to edit the hqplayerd.xml file. How to pull it out for editing? I created a login with my password according to the instructions in this topic, and I can connect via putty, hqplayerd.xml should I recycle via the command line? I wanted to pull the hqplayerd.xml file through WinSCP, but there is no access to the etc/hqplayer/hqplayerd.xml folder
-
I don’t understand how the Authentication tab works through the web interface and whether it is needed at all.
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If, when loading HQPE, a list of devices is displayed on the monitor via HDMI, is there enough data from these lines to form a line in hqplayerd.xml?
-
If the data from point 4 is not enough, what command should be used to enter the list of devices? Or will what is displayed in alsamixer be enough?
-
When I boot from USB for the first time, the list of output devices in the web interface does not appear immediately, if you press apply, line outputs and SPDiF outputs appear, but if you restart HQPE without even pulling out the USB drive, then when you next boot, you have to apply apply again so that the output devices can be seen again. Can this be saved or is it necessary for the system to boot from the HDD or SSD?
-
If the line input works, it will already be very good and it will be possible to think of a solution for automatically switching between linear / UPnP inputs, Jussi said this is quite solvable and it seems like I even understood mixing one type of input with UPnP.
This is all done to test the possibility of implementing a high quality sound system in a car, with DSP processing to a multi-band 8 channel system. It would be desirable that when it is necessary, the music plays with high quality, and when it is necessary, sound comes from the head unit when viewing youtube \ navigation \ games and other convenient things that are on android.
All good.
Thanks in advance for your replies.
Welcome to the most interesting thread in this hobby !
sudo nano /etc/hqplayer/hqplayerd.xml
You can change the default password using instructions on Embedded web page:
https://www.signalyst.com/embedded-install.html?
Yes, it will open a full new screen for hqplayerd.xml, if I understood correctly
Hmm I don’t follow this one. Try all the above first and report back.
Hmm normally if the ALSA and network ‘backends’ are ready, they will appear on the boot.
I only need to press ‘apply’ on the Config page if ALSA or NAA backends were not already booted/ready on HQP Embedded boot
Cool, will be interesting to see if you can get it working.
There are some very smart people here in this thread (not me) that will be happy to help you. I will try too with my limited knowledge !
This is really cool !
One problem you mentioned is audio delay. You cannot escape this with HQPlayer. The only thing that can be done with HQP audio delay is try to minimise it. Like minimum phase filters.
But the DSP takes time , so you will always have ‘lip sync’ issues with video unless you have some way to delay video.
Some LG TV’s I think allow you to adjust both + and - lip sync, delaying video by a small amount (limited memory available). But this is not common to find.
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