[PROBLEM] White noise occurs at random while playing

[hjheins]

I have newly installed a raspberry pi that is connected to a digital amplifier over usb from version 7.x to version 8.2.5
However, since I did so, I get very loud white noise seemingly at random while playing music.
It seems to happen especially often when playing ambient sleeping pill radio.
The remedy is to pause and start playing again.
however it is very annoying, and it did not happen in version 7
I tried to find infos in the logs, in dmesg and in moodutl -l, but there is no sign of anything being amiss in any of them.
How can I go forward in solving this?

thanks,

Hendrik-Jan

[Nutul]

I have newly installed a raspberry pi that is connected to a digital amplifier over usb from version 7.x to version 8.2.5
However, since I did so, I get very loud white noise seemingly at random while playing music.
It seems to happen especially often when playing ambient sleeping pill radio.
The remedy is to pause and start playing again.
however it is very annoying, and it did not happen in version 7
I tried to find infos in the logs, in dmesg and in moodutl -l, but there is no sign of anything being amiss in any of them.
How can I go forward in solving this?

thanks,

Hendrik-Jan

Hi,

first, I must say I have no clue about what might be going on, but you might try to look into MPD's log, which is the file /var/log/mpd/log
you might also want to enable verbose MPD log-level in the MPD configuration tab, bottom of the page.

[Tim Curtis]

What make/model amp?

[hjheins]

What make/model amp?

SMSL Q5 (the link is for the Pro; mine is the same but apparently already the older model without " pro")


@Nutul : thank you for the tip. I have set the mpd log to verbose, but it actually shows nothing out of te ordinary when it occurs.

[hjheins]

Maybe as an addition: I already tried to research this and I found mention of "snd-usb-audio.quirk_alias" for white noise between songs.
I tried that (adding a "snd-usb-audio.quirk_alias=..." ) to cmdline.txt, however that seems to have done nothing.

[TheOldPresbyope]

Maybe as an addition: I already tried to research this and I found mention of  "snd-usb-audio.quirk_alias" for white noise between songs.
I tried that (adding a "snd-usb-audio.quirk_alias=..."  ) to cmdline.txt, however that seems to have done nothing.

Umm, the whole quirks and quirk-alias thing is a bit messy. As I understand it,

• if a specific vendor-product (aka a device) has a "quirk" that has already been dealt with in the kernel (in a routine named quirks.c, naturally)
  
• then one can use the quirk-alias mechanism to apply the same solution to a different vendor-product
  

Here's the option definition in the ALSA docs

quirk_alias

    Quirk alias list, pass strings like 0123abcd:5678beef, which applies the existing quirk for the device 5678:beef to a new device 0123:abcd.

Did you have the two vendor_id:product_id pairs you need?

Regards,
Kent

[Tim Curtis]

I have newly installed a raspberry pi that is connected to a digital amplifier over usb from version 7.x to version 8.2.5
However, since I did so, I get very loud white noise seemingly at random while playing music.
It seems to happen especially often when playing ambient sleeping pill radio.
The remedy is to pause and start playing again.
however it is very annoying, and it did not happen in version 7
I tried to find infos in the logs, in dmesg and in moodutl -l, but there is no sign of anything being amiss in any of them.
How can I go forward in solving this?

thanks,

Hendrik-Jan

The symptom suggests some sort of hardware issue.

With hardware issues usually the only way to isolate the problem is to perform swapping for example connect the Pi to a different audio device or try a different USB cable. Something like that.

[hjheins]

I have newly installed a raspberry pi that is connected to a digital amplifier over usb from version 7.x to version 8.2.5
However, since I did so, I get very loud white noise seemingly at random while playing music.
It seems to happen especially often when playing ambient sleeping pill radio.
The remedy is to pause and start playing again.
however it is very annoying, and it did not happen in version 7
I tried to find infos in the logs, in dmesg and in moodutl -l, but there is no sign of anything being amiss in any of them.
How can I go forward in solving this?

thanks,

Hendrik-Jan

The symptom suggests some sort of hardware issue.

With hardware issues usually the only way to isolate the problem is to perform swapping for example connect the Pi to a different audio device or try a different USB cable. Something like that.

Hello Tim,

I actually expected that to be the case as well..
However It used to work before.
So before swapping out the hardware, I went back to Moode 7.3 as a test.
This seems to work flawless; no hissing/white noise whatsoever.

So I really think it is a software issue.
For now my solution is to keep this device on moode 7.3.

@TheOldPresbyope : you are right this is messy. I used the correct usbID from my device and a "quirk reference"  to a known good device. It made no difference whatsoever. But I didn't really expect it would, while the issue that was described to be solved with this, was white noise between tracks or when switching radio stations. As that was not my issue, it seemingly also was not the solution...

cheers,

Hendrik-Jan

[Tim Curtis]

I have newly installed a raspberry pi that is connected to a digital amplifier over usb from version 7.x to version 8.2.5
However, since I did so, I get very loud white noise seemingly at random while playing music.
It seems to happen especially often when playing ambient sleeping pill radio.
The remedy is to pause and start playing again.
however it is very annoying, and it did not happen in version 7
I tried to find infos in the logs, in dmesg and in moodutl -l, but there is no sign of anything being amiss in any of them.
How can I go forward in solving this?

thanks,

Hendrik-Jan

The symptom suggests some sort of hardware issue.

With hardware issues usually the only way to isolate the problem is to perform swapping for example connect the Pi to a different audio device or try a different USB cable. Something like that.

Hello Tim,

I actually expected that to be the case as well..
However It used to work before.
So before swapping out the hardware, I went back to Moode 7.3 as a test.
This seems to work flawless; no hissing/white noise whatsoever.

So I really think it is a software issue.
For now my solution is to keep this device on moode 7.3.

@TheOldPresbyope : you are right this is messy. I used the correct usbID from my device and a "quirk reference"  to a known good device. It made no difference whatsoever. But I didn't really expect it would, while the issue that was described to be solved with this, was white noise between tracks or when switching radio stations. As that was not my issue, it seemingly also was not the solution...

cheers,

Hendrik-Jan

Interesting. Trying to isolate which software component in the audio chain might be causing the issue would be difficult especially without the exact hardware.for a repro.

It would still be worthwhile to swap in a different model Pi if possible to see whether anything changes.

What model Pi are u using?

[hjheins]

I'm using a raspberry pi 3B
with a 7" raspberry approved screen attached and a 3.5A 5V powersupply.