[ishmael]

Looking for an affordable USB to SPDIF converter. I don't care if it spits out optical or coax. Must be USB powered only, no ac adapter.
 
I have tried 3 different ebay cheap models and none worked properly. I hope someone has one laying around that is known to work, that they will let go for a decent price. 
 
EDIT I am in the USA and it probably won't make sense for international deals on an item like this.

 

[PurpleAngel]

How about a Asus Xonar U3 USB sound card, $40.
Comes with S/PDIF 3.5mm optical output jack.
You do not have to use any of it's sound card features. 

 

[Sotiris]

i have hiface usb to coaxial at 50 euros.

 

[ishmael]

  How about a Asus Xonar U3 USB sound card, $40.
Comes with S/PDIF 3.5mm optical output jack.
You do not have to use any of it's sound card features. 

 
That might work, I will check other offers and let you know i a few days.