For the timebeing you could do:
playSoundOnNewMessage: function(dateObject, userID, userName, userRole, messageID, messageText, channelID, ip) {
if(this.settings['audio'] && this.sounds && this.lastID && !this.channelSwitch) {
if (channelID > 1000000000 && channelID < 1000001000) {
this.playSound(this.settings['soundError']); /// or another soundfile
return;
}