Audio is extremely distorted in Ubuntu Studio 21.10 using JACK on my Lenovo Thinkpad P15v Gen 2, using the built-in Intel Tiger Lake audio hardware.
It appears that all sound on the system is affected; LMMS, Hydrogen, Spotify, and even system sound effects (e.g. the 'blip' sound when adjusting volume) are all hyper-amplified into squelchy static.
Some apps, such as Spotify, become less distorted as I reduce the main volume, but I need to reduce the level to 15% or lower for the distortion to become inaudible.
Other apps, such as LMMS, retain their shrieking squelch no matter how far I pull back sliders in QASMixer.
The problem seems to be caused by some part of Ubuntu Studio's JACK configuration. I experience the same problem on a fresh install of Ubuntu Studio 21.10, and also on a vanilla install of Kubuntu where I have used the Ubuntu Studio installer. The Kubuntu installation did not have this problem before I ran the Ubuntu Studio installer.
I have tried changing JACK sample rate, buffer size, and periods with no noticeable change in the audio quality.
What can I do to fix this problem?