need help with .xa files on ps1 rom

[no idea for username]

im trying to change the audios of the game CTR (crash team racing.)

i have 2 questions:

1. how do i pack a lot of xa files into 1 big xa file like in the rom?

2. how do i change the audios of the game with my audios?

if you need more info: im using a bin file of the game, playing on an emulator.


if someone know how to do that please let me now!

(also im not so good in ps1 modding/coding)