no optical out on my imac whatsoever!

[ThomtheEditor]

Hi; i originally tried posting this over at macrumor's forums but no-one there seemed to be able to answer my problem!

I just got in my new imac; hooked up my audio via toslink & mini-to-optical adapter. This is running thru an optical switcher into my receiver, but i'm not getting any passthru at all.

Whenever i insert the cord/adapter combination the output in system preferences switches from internal to digital out; so it seems that it's recognizing it's an optical source output.

Checked at the end of cable for red light; coming thru super strong; checked audio settings in midi setup; only stereo is selectable, no multichannel.

Though maybe the cable was too long; plugged in an old PC usb sound card w/ optical out and it plays fine thru that. (i would just use that, but no mac drivers, so while the sound comes thru, no way to get true 5.1 output)

Tried going straight into receiver bypassing switcher, still nothing.

Any thoughts? Thanks in advance!

 

[ssm]

No sound on optical output on iMac

I am running an iMac (2007) with SP DIF optical on the audio mini port. The optical cable has a red light at the end and all connections are solid. I am connected to DAC which is connected to my stereo. The USB connection works fine. The DAC and cable work fine with optical when connect to my MacBook Pro.

Thus, I have isolated the problem to Snow Leopard. OS 10.6x does not allow the audio to pass over the optical port. I don't know why. The midi volume controls for the digital out are greyed-out and set to zero.

Suggestions?