Sound Out Problems

Sound out problems refer to a lack of sound coming from the internal speakers (located on the front of the unit directly below the display), external speakers (connected via the I/O panel to the speaker connector on the logic board), or both.

Possible Cause

Possible Fix

Control Panel setting is incorrect.

First, disconnect any external microphones, speakers or headphones. Next, verify that volume setting in Control Panel is adequate and that mute is not checked. Test the for sound coming from the internal speakers. Do you have sound now? Yes: If the initial sound out problem was with the internal speakers, the problem is solved. If you reconnect the external sound out device and it is not working, the problem may be with the external device itself or its cable. Replace the external microphone, speaker, or headphone in question with a known-good device. If the problem persists, replace the logic board.

No: Go to next step.

Corrupted PRAM.

Reset parameter RAM. Hold down <Command> <Option> <P> <R> during startup but before "Welcome to Macintosh" appears.

Loose speaker connection.

Verify that both ends of the internal speaker cables are attached securely.

Loose audio cable.

- Reseat the audio cable (922-4039) located on the divider panel, under the CRT.

Bad audio cable.

- Replace the audio cable (922-4039).

Bad speakers.

- Replace the speakers.

Bad logic board.

Plug known-good headphones or external speakers into the external jack. Do you get sound? Yes: Go to next step. No: Replace the logic board.

Bad headphone board.

- Replace the headphone board.

Was this article helpful?

0 0

Post a comment