Streaming Internet Audio "Static" Troubleshooting

English Multimedia
1

When streaming audio from the internet and using the site’s web player, I occasionally get an odd occurrence of a few seconds of audio being repeated over the top of new incoming audio. The repeated audio is not like an echo. It is more of the repeated audio being only half there but identifiable by the beat of the music or cadence of the vocals. The result sounds like static that is just as loud as the audio that is supposed to be playing. It may only last a few seconds or it may grind on until I get annoyed and reload the web player or web page. I am trying to find ideas about how to troubleshoot this problem.

What I do know:

  • The sound chip is built into the motherboard – an ASUS A88XM-A that uses a Realtek ALC887-VD and OpenSuse identifies as an FCH Azalia Controller using the snd-hda-intel driver.

  • I have been using this same motherboard since the OpenSuse 13.x days. The problem started in Leap 42 and has continued in Leap 15.

  • At the same time since the OpenSuse 13.x days, a lot of the sites I normally listen to have gone from MP3 to AAC audio format. The few sites I still listen to that have MP3 don’t seem to have the same problem.

  • The problem has popped up while using Firefox, Gnome Web (nee Epiphany), and once when streaming through Audacious. Local music files of any sort or files off the LAN server don’t have the problem.

  • Occasionally, the problem seems to be triggered by leaving the audio streaming in the background and navigating to a new web page that has a lot of activity (advertisements). Trying to repeat this as a “cause” usually doesn’t work.

  • I have tried to capture the problem as a sound file but having a recorder like Audacity open and idle seems to make everything behave.

  • The internet connection is DSL which seems to be fast enough – no skips or drop outs even with Youtube or Vimeo videos.

It seems as though the use of the AAC format as the culprit. Digging through Google shows a lot of discontent with PulseAudio and streaming but most of those postings are fairly old and PulseAudio has supposedly gotten a lot better of late. If anyone has any suggestions on where to look for trouble, I would appreciate hearing them.

2

Just to add a little. I finally got the “static” noise while streaming and I had Audacity open. I started recording and after about 15 seconds the sound went back to normal. I recorded about 21 seconds altogether. When I played back the Audacity recording, all 21 seconds were perfect! Under preferences in Audacity it shows that it is recording and playing back on the ALC-887VD (hw:1,0). I’m guessing this might be a hardware problem with the sound chip screwing up where it pipes audio to the line out jack but acts normally for internal sources. I might try getting an aftermarket sound card (do they still make them?) unless anyone has any ideas.

3

I seem to have solved the echo-static problem with the addition of an add-on sound card. Since I had an Asus motherboard, I got an Asus Xonar DG for just a few dollars. It’s a few years old (so is the motherboard) but it was new old stock. OpenSuse identified it right away and added the snd-virutoso module as the driver. Asus doesn’t make any Linux software for their sound cards so I can’t use any of the gee whiz special effects they tout for Windows. It has been running solidly for over 2 weeks now with no quirks.

The Asus motherboard uses a Realtek chipset while the sound card uses a C-media chipset (rebranded for Asus). Both chipsets seem to offer the same features – 2.1, 4, 5 channel, line in/out, and spdif in/out but the only difference in sound seems to be the C-media is louder at the same software volume setting.

It could be that the Realtek on the motherboard has a hardware problem but it might also have something to do with how the Realtek handles the snd-hda-intel driver. The Realtek chips might exactly meet the Intel specification or maybe they cut a few corners and this weirdness was the result.