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Thanks. ;)

Interesting that you say you don't see any light on your MBP. Another poster above says he can see light from his, and I'm certain on my MBP (in service at the moment) also *always* has visible light coming from it.

Weird. Mine's the latest 15 inch MBP, at the minute I'm on battery but I'm sure I haven't ever seen light coming out even when plugged in (I remember looking, because I have an old Sony CD player whose optical output is permanently on). I don't have any way to test it though - no cable and nothing to plug it in to!

Raises an interesting point though - how does the socket know an optical cable has been plugged in when there is no electrical connection? Or is there? - I don't think I've ever seen a 3.5 mm optical cable.
 
Seems pretty definitive to me then. The only other possibility I can see aside from a faulty port would be some other software disabling the audio out, but I don't think this is likely (and I'm not running anything else that I can see would do this.

Weird. Mine's the latest 15 inch MBP, at the minute I'm on battery but I'm sure I haven't ever seen light coming out even when plugged in (I remember looking, because I have an old Sony CD player whose optical output is permanently on). I don't have any way to test it though - no cable and nothing to plug it in to!

Raises an interesting point though - how does the socket know an optical cable has been plugged in when there is no electrical connection? Or is there? - I don't think I've ever seen a 3.5 mm optical cable.

I believe the mini-optical is slightly longer than a standard 3.5mm, which triggers something inside the port indicating a digital cable. It's unclear whether or not the light is visible when an optical cable isn't inserted (responses above are variable).
 
I believe the mini-optical is slightly longer than a standard 3.5mm, which triggers something inside the port indicating a digital cable. It's unclear whether or not the light is visible when an optical cable isn't inserted (responses above are variable).

Does your cable have an integral miniconnector, or is it one that attaches to a conventional Toslink connector? If the latter, when you tested it, did you have the miniconnector attached?
 
It's a standard toslink with a mini-adapter (removable). I don't have any other components that use the mini-adapter so I can't really test that bit, but looking at it you can see that it does nothing but adapt the cable to the port itself (you can look straight through it).

The mini-adapter also supports my theory that the port is bad, as inserting it by itself activates digital out on the Mini, but no light is emitted.
 
Only thing I can think that would be helpful is send me the Mac Mini then someone needs to put you out of your misery. Then that's that! :D
 
Appreciate your advice, but if there's no light from the optical port then spending hundreds on cables won't make any difference!
If System Preferences > Sound is showing "digital out" you should see
a red light in the miniToslink adapter and at the the end of any toslink
cable connected to the adapter.

The red light should be visible even if the audio output is "silent" or
idle. If no light is visible, the optical output is busted.

If there is a light but no response from a "known-good" receiver, the
toslink cable is probably too long. Apple's digital-optical outputs tend
to be wimpy, and often have problems with cable runs over 10-15 ft.
(You'll still see the red light plainly even when it's too weak to satisfy
the receiver).

Monster Cables are extremely effective at alleviating cash gluts and
evoking convulsions of hysterical laughter from electrical engineers.
OTOH, for transmitting optical or electrical signals, you'd be far better
to stick with www.monoprice.com.

LK
 
If System Preferences > Sound is showing "digital out" you should see
a red light in the miniToslink adapter and at the the end of any toslink
cable connected to the adapter.

The red light should be visible even if the audio output is "silent" or
idle. If no light is visible, the optical output is busted.

If there is a light but no response from a "known-good" receiver, the
toslink cable is probably too long. Apple's digital-optical outputs tend
to be wimpy, and often have problems with cable runs over 10-15 ft.
(You'll still see the red light plainly even when it's too weak to satisfy
the receiver).

Monster Cables are extremely effective at alleviating cash gluts and
evoking convulsions of hysterical laughter from electrical engineers.
OTOH, for transmitting optical or electrical signals, you'd be far better
to stick with www.monoprice.com.

LK

How many brothers and sisters do you have?
 
If System Preferences > Sound is showing "digital out" you should see
a red light in the miniToslink adapter and at the the end of any toslink
cable connected to the adapter.

The red light should be visible even if the audio output is "silent" or
idle. If no light is visible, the optical output is busted.

If there is a light but no response from a "known-good" receiver, the
toslink cable is probably too long. Apple's digital-optical outputs tend
to be wimpy, and often have problems with cable runs over 10-15 ft.
(You'll still see the red light plainly even when it's too weak to satisfy
the receiver).

LK

Thanks.

The cable is only 1.5m, Sound preferences definitely show as Digital Output when the cable is inserted, and no light is visible from the bare port or at the end of the cable when inserted.

Unless it's possible for software (or the OS) to have somehow disabled the optical out, I'm still leaning toward a faulty port. Shame it's no longer under warranty or I'd have just popped it into Apple for a look. Any guesses how much they'd charge for the port alone (does it necessitate a full logic board replacement?)

Cheers,

Tom
 
Thanks. ;)

Interesting that you say you don't see any light on your MBP. Another poster above says he can see light from his, and I'm certain on my MBP (in service at the moment) also *always* has visible light coming from it.

If it helps you any I use the digital out on my 24" aluminum iMac and see no light with the cable plugged in or not. The sound is working fine.
 
If it helps you any I use the digital out on my 24" aluminum iMac and see no light with the cable plugged in or not. The sound is working fine.

Are you sure you're using an optical cable? I can't imagine it working without any light being emitted. :confused:
 
Are you sure you're using an optical cable? I can't imagine it working without any light being emitted. :confused:

It's a TOSLINK to Mini-TOSLINK cable and the audio is working fine. Just so I know what it is I am supposed to be looking for and don't confuse you with misinformation you're referring a light on the socket itself on the Mac end, right?

If so I see no light with or without the cable inserted. I turned off the screen and all lights in my room and I'm sure there is no light being emitted.
 
UPDATE: OK, sorry, I think it is my stupidity just adding adding confusion to this thread. I have now confirmed that when digital audio data is passing down the cable (as in iTunes is playing a song) when I remove the digital cable from my home theater amp then indeed the light at the end of the optical cable (at the amplifier end) does indeed shine red.

But keep in mind just having the cable plugged in to the back of my iMac it is dark (at the amp end) unless data is passing through.

I'm sorry for misleading you. For some reason I was thinking that there was a light on the Mac end of the cable in the jack.
 
UPDATE: OK, sorry, I think it is my stupidity just adding adding confusion to this thread. I have now confirmed that when digital audio data is passing down the cable (as in iTunes is playing a song) when I remove the digital cable from my home theater amp then indeed the light at the end of the optical cable (at the amplifier end) does indeed shine red.

But keep in mind just having the cable plugged in to the back of my iMac it is dark (at the amp end) unless data is passing through.

I'm sorry for misleading you. For some reason I was thinking that there was a light on the Mac end of the cable in the jack.

Actually it is still of interest that no light is visible when nothing is playing. Though I'm reasonably certain iTunes was playing when I checked it yesterday, I'll try again tonight checking the amp end of the cable.

Of course, if the amp turns out to be the problem it'll probably cost more than the Mini to sort out! :rolleyes:
 
Actually it is still of interest that no light is visible when nothing is playing. Though I'm reasonably certain iTunes was playing when I checked it yesterday, I'll try again tonight checking the amp end of the cable.

Of course, if the amp turns out to be the problem it'll probably cost more than the Mini to sort out! :rolleyes:

My mini puts out red light through TOSlink whether audio is playing or not. (same mini as CaveMan)
 
My mini puts out red light through TOSlink whether audio is playing or not. (same mini as CaveMan)
My iMac does the same. When there's "nothing playing", the optical output
transmits "silence" -- which my external receiver detects and locks-on at
the data rate (44.1kHz or 48kHz) selected in AudioMidiSetup.app.

A "silent" digital output is entirely different than no digital output.

Also, my digital-optical output continues to transmit the red "silent signal"
even when I redirect all audio outputs to an external USB audio interface.
There doesn't seem to be any way to "disable" it (on a white C2D iMac).

Any guesses how much they'd charge for the port alone (does it necessitate
a full logic board replacement?)

If the optical-digital output is defective, I suspect an external USB audio
interface would be much less expensive than an out-of-warranty repair...

...and much more versatile, too,

LK
 
My iMac does the same. When there's "nothing playing", the optical output
transmits "silence" -- which my external receiver detects and locks-on at
the data rate (44.1kHz or 48kHz) selected in AudioMidiSetup.app.

A "silent" digital output is entirely different than no digital output.

Also, my digital-optical output continues to transmit the red "silent signal"
even when I redirect all audio outputs to an external USB audio interface.
There doesn't seem to be any way to "disable" it (on a white C2D iMac).



If the optical-digital output is defective, I suspect an external USB audio
interface would be much less expensive than an out-of-warranty repair...

...and much more versatile, too,

LK

Thanks for that. I had considered getting a USB or firewire audio interface but don't know much about them and have no idea where to find one. Any recommendations? (As a side note, it would be nice to use the FW400 port for something as my USB's are full!) :D
 
Anyone have any experience with the M-Audio Transit audio interface? It looks like it would give me an optical digital output (toslink) for about £50.

Failing that, anyone used a different device that they would recommend?
 
Doh! :D

Well thanks for posting anyway... seems experiences are definitely varied on the forum!

After reading these replies I decided to do a little further experimentation. With no audio playing I removed the toslink cable from my amp and the light was off. Once I start to play a song in iTunes the light comes on but I noticed that even stopping the song does not cause the light to go off again. Once the light is on it seems to stay on.

But just plugging the cable into the back of my iMac does NOT cause the light to come on at the amp end of the cable. It does not come on for me until I start playing audio.
 
Anyone have any experience with the M-Audio Transit audio interface?
Sorry, no experience with Transit, but I've been happy with other
M-audio products. Be sure to check the M-audio site for drivers;
they've been slow in releasing Leopard support for some products.

Also take a look at the Edirol/Roland UA-1EX. I don't know 'bout
UK availability, but US street prices (amazon.com) are about the
same for either Transit or UA-1EX.

LK
 
Thanks all!

Thanks everyone for your advice. I've reached the conclusion that the port is just faulty. It may have always been that way, but there's not much that can be done short of a repair (probably expensive) or an external interface.

I'm likely to go the external route for now as adapters are approx £40-50. I'll probably give the M-Audio Transit a go as it provides an optical output and I won't need to buy (yet another) cable as I would with the Edirol/Roland interface. I've checked the M-Audio site and they have a driver for 10.5.1 (which I'm going to assume will work fine on 10.5.2!)

I'll post back the results.

Cheers,

Tom
 
have you tried?

1. you said that it works fine with the mini plug to stereo rca. make sure to disconnect this as your receiver might default to rca if both rca and optical are plugged in on the same input.

2. go to your receiver set up and select digital/optical or such...

you are welcome!:p
 
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