Old MBP's headphone jack port don't always work with connected speakers.

Post by Ant
The old 13.3" MBP (mid-2012; Mac OS X v10.8.5/Mountain Lion)'s headphone
don't always work with various speakers (powered and non-powered).
Speakers seem to have no problems with his iPhone 6+ though. I looked at
MBP's headphone jack to see if it was dirty, but it looked OK? It was
hard to see inside though even with a flashlight.
Has anyone had this problem before? Thank you in advance. :)

A possible explanation is a faulty socket which is mistakenly activating
digital optical audio output rather than analog audio output. If it only
happens for some speakers, it might only be happening while the plug
from those particular speakers is connected - perhaps it is a slightly
different shaped plug which is falsely triggering the digital optical
output mode, or there could be a physical obstruction in the socket
which is preventing the plug from going all the way in, resulting in the
same effect.

If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

There is another way to tell: with the speakers plugged in but not
working, if the output is in digital mode and you try to use the
computer's volume adjustment keys, the on-screen popup to show the
volume adjustment will indicate that volume adjustment is disabled.
(That's because digital optical output is fixed level - volume needs to
be adjusted on the output device, not the computer.)

Similarly, the output volume adjustment in System Preferences >
Soundwill be greyed out, and the list of output devices in System
Preferences > Sound > Output should mention digital output rather than
"Internal Speakers" or "Headphones".

--
David Empson
***@actrix.gen.nz

Ant

2017-02-08 08:14:57 UTC

Post by David Empson

I forgot to mention that these are analog speakers only.

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

Post by David Empson
There is another way to tell: with the speakers plugged in but not
working, if the output is in digital mode and you try to use the
computer's volume adjustment keys, the on-screen popup to show the
volume adjustment will indicate that volume adjustment is disabled.
(That's because digital optical output is fixed level - volume needs to
be adjusted on the output device, not the computer.)
Similarly, the output volume adjustment in System Preferences >
Soundwill be greyed out, and the list of output devices in System
Preferences > Sound > Output should mention digital output rather than
"Internal Speakers" or "Headphones".

Ooh, we will check that. Will it say analog if analog speakers are
connected?

David Empson

2017-02-08 08:29:00 UTC

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

Post by David Empson
There is another way to tell: with the speakers plugged in but not
working, if the output is in digital mode and you try to use the
computer's volume adjustment keys, the on-screen popup to show the
volume adjustment will indicate that volume adjustment is disabled.
(That's because digital optical output is fixed level - volume needs to
be adjusted on the output device, not the computer.)
Similarly, the output volume adjustment in System Preferences >
Sound will be greyed out, and the list of output devices in System
Preferences > Sound > Output should mention digital output rather than
"Internal Speakers" or "Headphones".

Ooh, we will check that. Will it say analog if analog speakers are
connected?

If it is functioning correctly, the output should say "Internal
Speakers" if nothing is plugged in, or "Headphones" if an analog output
device is plugged in. It doesn't say "Analog" explicitly.

I don't have any digital output devices handy to check what it says for
digital, but my vague memory is that it did include "Digital" in the
description.

--
David Empson
***@actrix.gen.nz

Jolly Roger

2017-02-08 15:14:41 UTC

Post by David Empson
A possible explanation is a faulty socket which is mistakenly activating
digital optical audio output rather than analog audio output. If it only
happens for some speakers, it might only be happening while the plug
from those particular speakers is connected - perhaps it is a slightly
different shaped plug which is falsely triggering the digital optical
output mode, or there could be a physical obstruction in the socket
which is preventing the plug from going all the way in, resulting in the
same effect.

I forgot to mention that these are analog speakers only.

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

The output can still get stuck in digital mode; so you should look for
the red light to make sure it's not turned on.

--
E-mail sent to this address may be devoured by my ravenous SPAM filter.
I often ignore posts from Google. Use a real news client instead.

JR

Ant

2017-02-09 09:02:57 UTC

I forgot to mention that these are analog speakers only.

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

The output can still get stuck in digital mode; so you should look for
the red light to make sure it's not turned on.

OK. We will look for that. I never saw anything red. Does it show like a
red circle in that audio out hole with the audio cable connected?

Jolly Roger

2017-02-09 13:11:36 UTC

I forgot to mention that these are analog speakers only.

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

The output can still get stuck in digital mode; so you should look for
the red light to make sure it's not turned on.

OK. We will look for that. I never saw anything red. Does it show like a
red circle in that audio out hole with the audio cable connected?

Here are some YouTube videos that show it:

<https://duckduckgo.com/?q=mac+audio+red+light&iax=1&ia=videos>

--
E-mail sent to this address may be devoured by my ravenous SPAM filter.
I often ignore posts from Google. Use a real news client instead.

JR

Ant

2017-02-10 01:18:01 UTC

I forgot to mention that these are analog speakers only.

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

The output can still get stuck in digital mode; so you should look for
the red light to make sure it's not turned on.

OK. We will look for that. I never saw anything red. Does it show like a
red circle in that audio out hole with the audio cable connected?

<https://duckduckgo.com/?q=mac+audio+red+light&iax=1&ia=videos>

Interesting. I have never see these red lights before, but then I don't
use digital speakers. Same for "stuck" issue.

Jolly Roger

2017-02-10 02:10:28 UTC

I forgot to mention that these are analog speakers only.

Post by David Empson
If the output was stuck in digital mode you would see a red light in the
socket when looking into it, but if it only happens while a plug is
inserted, it may be hard to spot.

Hmm, we never saw this red light before but then we don't have any
digital speakers.

The output can still get stuck in digital mode; so you should look for
the red light to make sure it's not turned on.

OK. We will look for that. I never saw anything red. Does it show like a
red circle in that audio out hole with the audio cable connected?

<https://duckduckgo.com/?q=mac+audio+red+light&iax=1&ia=videos>

Interesting. I have never see these red lights before, but then I don't
use digital speakers. Same for "stuck" issue.

Like I said above, the port can get stuck in digital mode even if you
don't use digital speakers, which is why you should check it. ; )

--
E-mail sent to this address may be devoured by my ravenous SPAM filter.
I often ignore posts from Google. Use a real news client instead.

JR

Lewis

2017-02-10 23:51:28 UTC