Audio becomes distorted after some time

Hi, I am using the latest version build d626322 (1.2e) and now after some time audio starts to become distorted.
I have an excerpt in a 48 kb/s MP3 attached where the CW-note went from normal to distorted. I recorded it with Audacity but first found out while running wfview with wsjt-x. Toi be sure that neither wsjt-x or Audacity could be to blame. I ran wfview on it’s own with no extra apps needing audio output. The result was still the same, initially good but became distorted. I tried different audio output settings, sample rates and latencies but it remains happening now.
OS= Linux Mint (Mate-desktop) 20.04.3 LTS. Built wfview with the latest script and created new .conf. The .log is actually the audio file. For the moment, I have no – debug log file. I will post that when I have one. When looking at the sound settings I notice that the Alsa plugin of WFview starts flashing. I use pulse as audio setting in WFview.
RX=R8600 and connection over LAN.
73 Peter - PA0PJE
wfview-distorted_mp3.log (749.1 KB)

Hi Peter.

Have you tried RT Audio as that was specifically added due to issues with QT Audio on certain Linux distributions? You can select from QT Audio, RT Audio or PortAudio using the combobox to the right of the audio device comboboxes.

73 Phil M0VSE

Hi Phil,

No, but I do now…
I was lucky it occurred again while running --debug and when the problem started again I saw lots of messages:

ALSA lib pcm.c:8526:(snd_pcm_recover) underrun occurred

in the terminal.
Switching to RTaudio does nothing, no audio, but PortAudio does.
I’ll keep an eye on this, thanks for your quick answer.
73, Peter - PA0PJE

Ah, RT Audio switches also to an HDMI audio device in my video card, which is disabled in the OS. With RT Audio you also need the Audio Input and Output device set to “Default”. At least this is true for my PC… and disconnect first :slight_smile:
No glitches heard any more.

Hi Peter.

That’s good! Rt Audio “should” work but I have found that the audio device names can be slightly different with the different audio APIs, so you may need to re-select the audio devices once you have changed API.

73 Phil