[joropito]

I guess the only way to do that is to force people to use a custom voicerecord command (+startvoice) and implement at FM_Voice_SetClientListening your own control.

You have to block every voice communication for users not using that command.

PHP Code:

#include <amxmodx>
#include <fakemeta>

#define get_bit(%1,%2)     ( %1 &   1 << ( %2 & 31 ) )
#define set_bit(%1,%2)    %1 |=  ( 1 << ( %2 & 31 ) )
#define clear_bit(%1,%2)    %1 &= ~( 1 << ( %2 & 31 ) )

new g_PlayerVoice

public plugin_init()
{
    register_clcmd("+startvoice", "player_startvoice_on")
    register_clcmd("-startvoice", "player_startvoice_off")

    register_forward(FM_Voice_SetClientListenting, "setclient_listening")
}

public player_startvoice_on(id)
{
    set_bit(g_PlayerVoice, id)
    client_cmd(id, "+voicerecord")
    return PLUGIN_HANDLED
}

public player_startvoice_off(id)
{
    clear_bit(g_PlayerVoice, id)
    client_cmd(id, "-voicerecord")
    return PLUGIN_HANDLED
}

public setclient_listening(receiver, sender, bool:listen)
{
    if(!is_user_connected(receiver) || !is_user_connected(sender) || (receiver == sender)
      return FMRES_IGNORED

    if(!get_big(g_PlayerVoice, sender))
    {
        engfunc(EngFunc_SetClientListening, receiver, sender, false)    // Can't talk because is not using +startvoice
        return PLUGIN_SUPERCEDE
    }

/*
      put your code here
      you can modify bool:listen depending on what you want and then call SetClientListening + return SUPERCEDE

      To change behavior (mute, permit, etc)
          engfunc(EngFunc_SetClientListening, receiver, sender, listen)
          return FMRES_SUPERCEDE
*/

    return FMRES_IGNORED
}