Did you ever try to save the preferences of PegasosMixer version 1.8?
It doesn't work (ac97mixer.library fault), you need this small script.
Balances are allways ignored.

Example:
rx FixMixer outputs.headphone=max,on

 PERMSSN    UID  GID    PACKED    SIZE  RATIO METHOD CRC     STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]                  485    1191  40.7% -lh5- bdb0 Oct  5 00:59 FixMixer.rexx
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total         1 file      485    1191  40.7%            Oct  5 14:00