Set sample data in a clip. The samples should be floats ranging from 0.0f to 1.0f (exceeding these limits will lead to artifacts and undefined behaviour).

The sample count is determined by the length of the float array. Use offsetSamples to write into a random position in the clip. If the length from the offset is longer than the clip length, the write will wrap around and write the remaining samples from the start of the clip.

	// Read all the samples from the clip and half the gain
	function Start () {
			var samples = new float[audio.clip.samples * audio.clip.channels];
			audio.clip.GetData(samples, 0);
			for (var i = 0; i < samples.Length; ++i)
				samples[i] = samples[i] * 0.5f;
			audio.clip.SetData(samples, 0);
	}

using UnityEngine;
using System.Collections;

public class Example : MonoBehaviour {
    void Start() {
        float[] samples = new float[audio.clip.samples * audio.clip.channels];
        audio.clip.GetData(samples, 0);
        int i = 0;
        while (i < samples.Length) {
            samples[i] = samples[i] * 0.5F;
            ++i;
        }
        audio.clip.SetData(samples, 0);
    }
}

import UnityEngine
import System.Collections

public class Example(MonoBehaviour):

	def Start() as void:
		samples as (float) = array[of float]((audio.clip.samples * audio.clip.channels))
		audio.clip.GetData(samples, 0)
		i as int = 0
		while i < samples.Length:
			samples[i] = (samples[i] * 0.5F)
			++i
		audio.clip.SetData(samples, 0)