The following demo plays a different FX every time you press ‘1’

        org #8000

        di

        ;Initializes the music.
        ld hl,Music
        xor a                                   ;Subsong 0.
        call PLY_LW_Init

        ;Initializes the sound effects.
        ld hl,SoundEffects
        call PLY_LW_InitSoundEffects

Sync:   
        ei
        nop
        halt
        halt

        di

       ld bc,63486         ; keyboard row 1-5/joystick port 2.
       in a,(c)            ; see what keys are pressed.
       rra                 ; outermost bit = key 1.
       jr nc, playfx
        ; if carry then no key pressed

        
       xor a
       ld (keypressed),a
       jr playmusic

playfx:

       ld a,(keypressed)
       and 255
       jr nz,playmusic

        ld a,(SelectedSoundEffect)
        inc a
        ld (SelectedSoundEffect),a
        cp 8
        jr nz, playfx2
        xor a
         ld (SelectedSoundEffect),a
playfx2:
       ld c,1
       ld b,0          ;Full volume.
       call PLY_LW_PlaySoundEffect
       ld a,1
       ld (keypressed),a

playmusic:      
        call PLY_LW_Play
    
        jp Sync
        
        ret

SelectedSoundEffect: db 1                       ;The selected sound effect (>=1).

KeyboardMaskLine0: db 255
KeyboardMaskLine1: db 255
KeyboardMaskLine2: db 255
KeyboardMaskLine5: db 255
keypressed: db 0

Player:
        ;IMPORTANT: enables the sound effects in the player. This must be declared BEFORE the player itself.
        PLY_LW_MANAGE_SOUND_EFFECTS = 1
        
        ;Include here the Player Configuration source of the songs and sound effects (you can generate them with AT2 while exporting the them).
        ;If you don't have any, the player will use a default Configuration (full code used), which may not be optimal.
        ;If you have several songs, include all their configuration here, their flags will stack up!
        ;Warning, this must be included BEFORE the player is compiled.
        ;include "../resources/MusicDeadOnTime_playerconfig.asm"
        ;include "../resources/MusicMolusk_playerconfig.asm"
        ;include "../resources/SoundEffectsDeadOnTime_playerconfig.asm"
        

        include "../PlayerLightweight_SPECTRUM.asm"

Music:
        ;Choose a music, or maybe silence?
        include "../resources/MusicDeadOnTime.asm"                     ;25Hz! Change the flag at the top to 1.
        ;include "../resources/MusicEmpty.asm"
        ;include "../resources/MusicMolusk.asm"                         ;50Hz! Change the flag at the top to 0.

SoundEffects:
        include "../resources/SoundEffectsDeadOnTime.asm"