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mkerr64 · Jan 25, 2009, 02:11 AM

Hi there

I have the logitech z5500 plugged into my MP. it was always been working for me until today.
I placed a microphone into one of the side inputs and did not work.
After that i tried playing music and anything with sound and nothing came out of them.
I have gone into preferences and changed the internal speakers, line out , digital and none of them seem to work.

I even tried all of the inputs on the speakers
I am using a fiber optic cable to transmit the sound to the speakers

Any ideas how to fix this?

Thank you

Spheric Harlot · Jan 25, 2009, 12:00 PM

You've got an S/PDIF optical cable running from the Mac Pro optical output (on the rear) to the input of the z5500?

And you tried pluggin a microphone into the Mac Pro's analog audio input? (This part CANNOT work, because the input is a LINE input, not a mic input.) I assume you messed around with all sorts of settings trying to get this working?

In system preferences' Sound panel, if you change to internal speakers, what does the mute button on your keyboard do? Does the volume adjustment work - even if no sound comes out?

Open up Applications/Utilities/Audio-MIDI Setup - What is your "System" output set to? What's the sample rate for that device set at?

If you've set it to digital out, make sure it's at 44.1kHz - the z5500 probably doesn't understand any higher sample rates.

mkerr64 · 01:39 PM

1) S/PIDF optical cable is correct

2) when i put the microphone into the jack, it simply did not work. i did not mess around with the settings.

3) I can play music out of the actual MP however, when i increase or decrease the volume an image with a cross comes out with a faded image of the speaker. in other words, i cannot adjust the loudness

(digital out aka z5500)

4)

where do i change it to 44.1kHz?

Spheric Harlot · Jan 25, 2009, 03:33 PM

See where it says "Properties For:" in the Audio device pane?

Change that so that you're actually looking at your digital out, and fiddle with the settings.

And since the Line In is set to 96000 Hz, it's very likely that so is your digital output.

The Logitech z5500 understands 96kHz, but only in PCM stereo or DTS, and probably only in 24 bits. 96 kHz at 16 bits makes no sense at all (since 24-bit audio makes for a lot bigger quality difference than 96kHz).

mkerr64 · Jan 25, 2009, 06:09 PM

I changed the Audio Output to Digital Out
Format: 96000.0 Hz 2ch- 24 bit

is that right?

The sounds finally comes out of the speakers- including optical

seanc · Jan 25, 2009, 06:11 PM

No, you want it on 44100.0 hz.

Spherics post confused me a bit too.

mkerr64 · Jan 25, 2009, 06:17 PM

Great !!
Thank you very much Spheric Harlot and seanc

Spheric Harlot · Jan 26, 2009, 11:07 AM

Originally Posted by seanc

No, you want it on 44100.0 hz.

Spherics post confused me a bit too.

There's absolutely no harm in running it at 96 kHz.

Most audio is at 44 kHz though.

seanc · Jan 26, 2009, 04:05 PM

OK.

I checked mine and that was what it was set on. I thought you might have gone off on a tangent talking about how the Z5500 can handle 96kHz - because before that we were talking about 44kHz.

Spheric Harlot · Jan 26, 2009, 05:40 PM

Originally Posted by seanc

. I thought you might have gone off on a tangent talking about how the Z5500 can handle 96kHz

It can.

But only with 24 bits, and only in DTS or PCM stereo, apparently.