Why isnt OnTriggerEnter Tags working.

So i have the script working but i would like some polish on it as it has a slightly annoying effect. This is what i had working. Its a hover bike that has four thrusters in each corner that also set this off. So it plays my first time audio as well as my other time 4 times.

var firstTime : AudioClip;
var otherTime : AudioClip;
var isfirstTime : boolean = true;


function OnTriggerEnter(){
	if(isfirstTime == true){
		audio.PlayOneShot(firstTime);
		isfirstTime = false;
		ScoreManager.finishgame += 1;
		}
	else{
		audio.PlayOneShot(otherTime);
		}
}

And this is my attempt to stop it doing that, it plays the first time when i tag a part of the bike with Player but then it doesnt play the other time. ROAR whyyyy

var firstTime : AudioClip;
var otherTime : AudioClip;
var isfirstTime : boolean = true;


function OnTriggerEnter(other:Collider){
	if (other.gameObject.tag == "Player"){
		if(isfirstTime == true){
			audio.PlayOneShot(firstTime);
			isfirstTime = false;
			ScoreManager.finishgame += 1;
		}
	}
	else{
		if (other.gameObject.tag == "Player"){
			audio.PlayOneShot(otherTime);
		}
	}
}