Apple LATE 2009 manual Audio Built-in Speaker Has Distorted Sound, M09

Audio: Built-in Speaker Has Distorted Sound

Quick Check

Symptoms	Quick Check
Audio: Built-in Speakers Have	1.	Launch System Preferences and select Sound/
Distorted Sound		Output options. Verify that the sound output
• No audio from one or both		option is set to system’s internal speakers and
speakers.		that the balance control is set to the center
		position.
• Audio from speakers distorted
	2.	Obtain known good high quality sound file
		or use iTunes music store sound samples to
		evaluate sound quality. Verify suspect sound files
		on another system to determine whether the
		distortion is caused by the system or the sound
		file.
	3.	Set volume control to mid-range. Overdriving the
		built-in speakers can cause distortion.

Deep Dive

Check		Result	Action	Code
1.	Launch System Preferences and	Yes	Speaker and amplifier
	select Sound/Output options.		circuitry OK. Go to step 3.
	Set speaker balance to the
		No	Distortion detected in
	middle, then play a sound file.
	Verify that sound is generated		speaker. Go to step 2
	by the speaker and that the
	sound quality is acceptable.
2.	Connect external speakers or	Yes	Suspect bad speaker. Go to
	headphones to Headphone		step 3.
	Out port then play a sound
	file. Verify that sound quality is
	acceptable.
		No	Audio CODEC or amplifier	M09
			issue suspected. Replace
			audio board. Retest.
3.	Inspect speaker cones and	Yes	Replace damaged speaker.	M09
	speaker connection cable for		Retest.
	damage. Does the speaker have
		No	Go to step 4.
	visible damage.

2009-11-03 Mac mini (Late 2009) Symptom Charts — Input/Output Devices  64