Home Page Forums MAME Non-Windows MAME Support Audio pops and crackles on Ubuntu

Debug builds are also much more likely to have audio dropouts.

Wow! Did you try deleting your ~/.pulse directory and restarting Pulseaudio? I think there was a lot of changes since 18.04. I'm on Ubuntu as well. I would do a thorough investigation on the various audio mixer settings available through Alsa and Pulseaudio, there are various GUIs and ncurses interfaces to look at these settings. There might be something boosted beyond the normal limits.

Did you figure out what was wrong? I was just messing around the other day and remembered that machines like qbert and asteroids make a lot of clicking sounds and have pulseaudio underruns if "waitvsync" is on. With "-nowaitvsync" the clicks and underruns go away but I get screen tearing which I really hate!

Hi Mocha,

I was going to experiment with a few different systems and OSes to see if it was any difference in hardware. Unfortunately, I don't have the room to set up a bunch of my systems at the moment.

I did try a laptop that had a core i5-4300U @ 1.90 ghz with ubuntu 22.04.1 and it didn't seem to have a lot of the underruns.

lspci says that it has a "Haswell-ULT Integrated Graphics Controller" and a "Haswell-ULT HD Audio Controller".

It also has the mockingboard showing "activity" when it's idle.

Maybe other processes on the system are causing problems.



I wonder if it has something to do with other tasks running on the system like Firefox and having a bunch of windows and tabs open.,

Try xorg vs wayland
Try different cpu / sound hardware.


Hmmmm. I fired up audacity to monitor and record the sound, dropping out different channels in the Slider Controls and I noticed that leaving one channel of the AY8913 running it seems to create an intermittent signal: (edit: with -video opengl and the Slider Controls window active)





Left of the bar is it set to 2.0, right of the bar is it set to 1.0.

and if I turn the sound way up on my headphones, it sounds very poppy and crackly.

Putting mame on pause, then playing the sound recorded on a loop in Audacity with Shift+Space the sound is exactly the same pops and crackles.


Interestingly turning on channel 1 + 2 will give you a "straight line".



right of the line is channel 1 and 2 set to 1.0 with channel 0 set to 0.0.

edit:

Hmmmm. I noticed that it was kind of intermittent when I had the slider window open with all of the UI text under -video opengl.

Moving to -video bgfx with -video_backend opengl audacity records a straight line.

Toggling the UI with TAB and all the slider text (with -video opengl), you can see the levels "bouncing" slightly in pavucontrol.