After kernel update: Debian12 ASL3 Distortion/choppy audio on SimpleUSB TX audio especially telemetry

Also just a casual and quick reminder: Issuing the test tone command: *904 (by default) after enabling it in rpt.conf REALLY makes it stand out versus listening to or waiting for telemetry/audio where it can also be heard.

I’m so glade I have seen this thread. I have the same issue and thoute I had created a problem with my node…

Hopefully a fix can be found.

I too have noticed this distortion on kernels .29 and .30 on my radio-less node. I think you guys already have established this, but Backing up to .28 does restore ā€œnormalā€ operation.

Working version:

********** AllStarLink [ASL] Version Info **********

OS            : Debian GNU/Linux 12 (bookworm)
OS Kernel     : 6.1.0-28-amd64

Asterisk      : 20.11.0+asl3-3.2.0-2.deb12
ASL [app_rpt] : 3.2.0

Installed ASL packages :

  Package                         Version
  ==============================  ==============================
  asl3                            3.6.0-1.deb
  asl3-asterisk                   2:20.11.0+asl3-3.2.0-2.deb12
  asl3-asterisk-config            2:20.11.0+asl3-3.2.0-2.deb12
  asl3-asterisk-modules           2:20.11.0+asl3-3.2.0-2.deb12
  asl3-menu                       1.11-1.deb12
  asl3-update-nodelist            1.5.1-1.deb12
  dahdi                           1:3.1.0-2
  dahdi-dkms                      1:3.4.0-4+asl
  dahdi-linux                     1:3.4.0-4+asl

Simply changing to .29 or .30 brings back the distortion problem.

I’ll be glad to help if you need additional testing points.

How are you ā€œnoticingā€ it on radio-less nodes and what precisely do you mean by ā€œRadio-lessā€?
Are you meaning a hub node (no hardware) or do you mean a system with a USB adapter (hardware) but not radio?

I have two hubs (no hardware) both running on -30 and I cannot create distortion. Both systems are, however, virtual machines. Is your ā€œradiolessā€ node hardware?

I should mention I can replicate the issue on hardware and a USB interface. I’m working on the right incantations to hold back the -29 and -30 kernels.

Sorry for the incomplete info. I’m running a C-media (CM119) usb adapter connected to an amp.
Basically this:

How did I Notice: sounds just like the video when time announcements and/or voice traffic is present on the attached speaker. I have also noticed similar distorted audio from my MIC on the repeater I’m connected to (via allstar).

Is the choppy audio only Simple USB ??? de nu5d

For me, yes only simple usb and only on >.28 kernel

Are you saying this because you tried USBRadio and did not have the issue? Or just reporting you’re using SimpleUSB.

I’m only using simpleusb. Should I give USBRadio a try?

Not necessarily. You said ā€œonlyā€ SimpleUSB implying you’d tested USBRadio.

OK - NOW I have tested both. It’s present on both

Please try running this and see if your system reverts to a clean state:

 wget -O- https://repo.allstarlink.org/hotfix/asl3-deb12-kernel28-fix.sh | sudo bash -x

Well, yes that’s just putting me back at .28 (which is what I was doing in GRUB manually).
It works perfectly in .28. The noise is present in .29 and .30 kernels.

It acts like there is a USB throughput issue in these kernels, too much jitter getting the audio down the USB pipe.

That’s exactly what it’s supposed to do. Set your kernel to 6.1.0-28 and pin it there until we can figure out the problem.

I tried the ā€œwget -O- https://repo.allstarlink.org/hotfix/asl3-deb12-kernel28-fix.sh | sudo bash -xā€ and it appears it downgraded the node to -28 but I’m getting an error with the USB tuning when I rebooted (which I did three times):

I’ll leave it in this state in case you need me to check something. - Tom

After running the wget, I’m also getting an error with USB tune and the USB interface board has stopped working completely?

https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1093390

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Please provide the output of:

lsmod | grep dahdi
grep pseudo /var/lib/asterisk/messages
# uname -a
Linux node460182 6.11.10+bpo-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.11.10-1~bpo12+1 (2024-12-19) x86_64 GNU/Linux

The 6.11 kernel from bookworm-backports works fine.