How to hear sounds from line-in jack? (fwd)

[Linux for blind general discussion]

> ---------- Forwarded message ----------
> Date: Wed, 23 Nov 2022 21:36:53 +0800 (CST)
> From: 高生旺 <coscell at gmail.com>
> To: slint at freelists.org
> Subject: How to hear sounds from line-in jack?
> 
> Sounds from line-in can be recored, but how to hear them in time?
> Which console command can be used for this purpose?

Hi, 

Not all sound cards are capable of simultaneous
input and output (duplex operation.)

Also, most distributions have pulseaudio installed
as a layer of over ALSA. 

One solution using ALSA (with PA disabled) would be
using ecasound.

ecasound -i alsa,default -o alsa,default

You could also try alsahw,0 instead of
alsa,default, or alsahw,1, etc. depending
on the number of your sound card. You
can also use the name.

For details use `cat /proc/asound/cards`.

Have fun,

Joel


-- 
Joel Roth