Solved Recent Audio Distortion

[jrm@]

I've noticed some recent audio distortion on two different desktops running 10.2. Nothing in the base of these systems has been updated for months and I don't recall recently changing any relevant settings. This happens in Firefox, Mplayer or MPV. Here is an example video where the problem is quite noticeable at the beginning when orchestral music is playing. I guessed the problem was with a recent upgrade to the ffmpeg package, but downgrading to 2.8.5 made no difference. Have you noticed this problem?

 

[jrm@]

Here is another video with distorted audio. It's Richard Feynman Ode To A Flower. The same video played on other devices (e.g., an Android phone) sounds much better.

 

[jrm@]

User error. A few months ago I had added the following lines to /etc/sysctl.conf to make the laptop speakers louder. It worked in that the audio was louder, but at the cost of mild distortion.

hw.snd.vpc_0db=15
hw.snd.vpc_autoreset=0