jackd sound

FreeBSD has a very good sound layer.

In order to edit audio files audacity is a good tool: https://www.freshports.org/audio/audacity/

It requires jackd to be running: https://www.freshports.org/audio/jack/

Message from jackit-0.125.0_3:
It is recommended to run Jack with real-time priority (-R).

The recommended way to start Jack is to add the following
lines to /etc/rc.conf:

jackd_args="-R -doss -r{sample-rate} -p1024 -n3 -w16 \
	    --capture /dev/dsp{N} --playback /dev/dsp{N}"

- your-jack-user: is the user who is going to use jack; currently
		  only one user is supported
- sample-rate: can be 44100, 48000, etc.
- /dev/dsp{N}: your OSS devices, usually /dev/dsp0

Please note that the port option COOKEDMODE is "on" by default, which
makes your system to automatically scale the sample-rate between
Jack and audio hardware. One reason COOKEDMODE=on is because
Jack's OSS driver doesn't support some sample-rate and hardware
combinations when COOKEDMODE=off. To achieve the best sound quality
please make sure your hardware natively supports the sample-rate set
in jackd_args, and set COOKEDMODE=off.

Relevant rc.conf part in my setup:

# jackd
jackd_args="-R -doss -r44100 -p1024 -n3 -w16 --capture /dev/dsp0 --playback /dev/dsp0"