RAM problem loading a lot of sound files using WWW.

I am using WWW in csharp to load thousands of sound clips one at a time stored in a folder on my computer. Every time I load a sound using WWW www = new WWW(file path); and play it, memory usage grows. Is there anyway to clear the previously loaded files from memory. After around 1600 loaded and played files, nothing can be loaded.

Here is my csharp code:

using UnityEngine;
using System.Collections;
using System.IO;

public class audioLoad : MonoBehaviour {
	
	public string path = "c:/oggunity/"; 
	public bool randomize = true;
	public float minWaitTime = 0f;
	public float maxWaitTime = 5f;
	public float waitTime=0f;
	public float counter =0f;
	public int actualClip=0;
	public string[] files;
	WWW wwwFile;
	private bool gate=true;
	private int previousClip;
	public string actualFile;
	
	// Use this for initialization
	
	void Start () {
	
	files=Directory.GetFiles(path,"*.ogg");
	
			
	}
	
	// Update is called once per frame
	void Update () {
		
		if(!audio.isPlaying && audio.clip.isReadyToPlay)
		{	
			if (gate==true)
			{	
				
				if(randomize)
				{
					do{actualClip=Random.Range(0,files.Length);}while(actualClip==previousClip);
					previousClip=actualClip;
				}
				else
				{
					if (actualClip<files.Length-1)actualClip++; else actualClip=0;
					previousClip=actualClip;
				}
				
				wwwFile = new WWW ("file:///"+files[actualClip]);
				Debug.Log("new file loaded");
				actualFile=files[actualClip];
				gate=false;
			}
			
			if (counter<waitTime)
			{
				counter+=Time.deltaTime;
			}
			else
			{
				audio.clip=wwwFile.audioClip;
				audio.Play();
			}
			
		}
		
		if(audio.isPlaying && gate == false)
		{
			gate=true;
			counter=0f;
			waitTime=Random.Range(minWaitTime,maxWaitTime);
			
		}
		
	}
	
	
	
		
	
	
		
}

To free the memory :

Resources.UnloadUnusedAssets();