[Fuck For Fun]

Tell me if that's what your request:

/* Plugin generated by AMXX-Studio */

#include < amxmodx >

#define PLUGIN "New Plug-In"
#define VERSION "1.0"
#define AUTHOR "author"

new g_pAutoSound;

new const g_szWinTeam[] = "***/XXX.mp3"; // *** That name of Folder after sound/ + change the name XXX to name mp3

public plugin_init() {
    register_plugin(PLUGIN, VERSION, AUTHOR)
    
    register_logevent( "EventRoundEnd", 2, "1=Round_End" );
    
    g_pAutoSound = register_cvar( "amx_autosound", "1" );
}

public plugin_precache()
{
    precache_sound( g_szWinTeam );
}

public EventRoundEnd()
{
    if (!get_pcvar_num( g_pAutoSound ) ) // dont sure if that will work = I retired two months ago from programming
                return;
        
    client_cmd( 0, "spk ^"%s^"", g_szWinTeam );
}


// if my code wrong that another way

//    new players[ 32 ], pnum;
//    new tCount, ctCount;
//    get_players( players, pnum, "c" );
    
//    for( new i = 0; i < pnum; i++ )
//    {
//        if( !is_user_connected( players[ i ] ) )
//            continue;
        
//        switch( cs_get_user_team( players[ i ] ) )
//        {
//            case CS_TEAM_T: 
//                client_cmd( i, "spk ^"%s^"", g_szWinTeam );
            
//            case CS_TEAM_CT: 
//                client_cmd( i, "spk ^"%s^"", g_szWinTeam );
//        }
//    }