Asterisk 16.16.1 and mpg123 version 1.26.4 have issues with asterisk modules that depend on mpg123.
(my scenario use a raspberry pi4)
The problem happens because the output of mpg123 does not render by default the 16bits expected by asterisk, causing a very strong noise or hiss in the audio.
To solve this, I developed a technique that interfaces asterisk and mpg123, passing a parameter that forces the bit depth to 16. Solving everything like magic:
# mv /usr/bin/mpg123 /usr/bin/mpg123A
# vi /usr/bin/mpg123
write the content:
/usr/bin/mpg123A -e s16 “$@”
# chmod +x /usr/bin/mpg123
Ready! problem solved.