[johnzoidberg]

I recently noticed that after I unplug my headphones from my iMac G5, sound does not come out of its built-in speakers until after I restart or put the iMac to sleep, and then wake it back up again. Upon closer inspection, I opened the Sound preference pane and noticed after I unplug the headphones, instead of switching from "Line Out" to "Built-in Speakers" in the Output tab, it switches to "Built-in Audio (spdf)" instead, like I somehow triggered the optical sensor or whatever in the combo port during the process of unplugging the headphones.

Does anyone have a similar problem? It's not that major, but it's really annoying.

[MaxPower2k3]

it's happened to me. i just plugged in and unplugged the headphones a few times and it worked. it only happened once

[Ozzpot]

Mine does this too. It has happened a few times.

Many 3.5mm jacks have a built-in switch, a delicate physical structure inside the unit that is pressed "on" when something is plugged in. Usually, as this type of socket is most often used for audio applications, is used to turn off the speakers. When the plug (e.g headphones) is removed, the switch should be released to the "off" position, thus turning the speakers on again.

It is not uncommon, especially after a couple of years, for this mechanism to become "sticky", i.e the switch does not always physically switch back when a plug is taken out. There is not much you can do about it. The unit needs replacing, but in most cases it is a mere annoyance rather than a major problem.

Unfortunatley the new iMacs do seem prone to this little fault from new. If it bothers you that much you could get Apple to fix it, but the problem may always re-occur. It is a known issue with these little buggers I'm afraid.

[johnzoidberg]

Is this a common issue on the new iMacs?

Is this an actual hardware issue, because after cutting off the power (restart, or sleeping and waking the unit back up) to the iMac after unplugging the headphones, seems to "switch" or "reset" the audio back to the built-in speakers?

[Thain Esh Kelch]

Hmmm... Thats pretty annoying.. :/ Im seeing the same problem on a new iMac 2 Ghz.

[Ozzpot]

I have seen this a lot on other products, mostly cheaper brands of walkman, and usually only after a few months of "wear and tear".

The fact that new iMac G5s seem prone to it indicates rather worryingly that Apple may be cutting corners in build quality. :-(

[Eriamjh]

The problem is that the connector doubles as an electrical connector for standard headphones and an optical connector for SPDIF digital audio.

It probably is not sensing the headphone connector, but the contact is dirty which makes it think that since a headphone connector is not inserted (there would be an electrical impedance change), that an optical cable is plugged in.

Somehow, you need to clean the connector. Good luck doing that without messing up with optical port itself.

[MaxPower2k3]

we (all of us that have had this problem) need to clean our brand new line out connectors?

[Eriamjh]

Originally Posted by MaxPower2k3

we (all of us that have had this problem) need to clean our brand new line out connectors?

Good point. It's probably the cause of a defective component. Perhaps the combination headphone/SPDIF connector just isn't ready for prime time?

[Thain Esh Kelch]

If someone contactes Apple about this problem, could that person plz put their response into this thread?

[johnzoidberg]

I'm not sure if this issue has to do with a "sticky" contact. Because when I unplug my headphones, no sound will come out of the speakers, but when I put the iMac to sleep, and wake it back up, sound will come out of the speakers again, almost like the sound circuitry is being "reset."

[Thain Esh Kelch]

I am pretty sure most of the circuitry is being reset when you wake up from sleep. Sleep is a power-saving mode, so no power should be running through most areas..

[yngram]

Can you see/select the internal speakers in the sound preference pane?

[ssray23]

I too am facing, exactly the same problem on my relatively new imac G5 (Rev B) loaded with Tiger 10.4.2.
Seems it's a common problem with the new iMacs.