Wadia 581iSE ST glass output problem

I have my Wadia 581iSE hooked up to Sonic Frontier Processor 3 as the DAC using ST (glass optical). The SF can lock 44.1kHz, but no audio whatsoever. AES/EBU is okay as well as TOSLINK. I really want to use the ST since it's the best performance. I've disable all the clocklink stuff under the configuration. Can anyone please help? Thanks.
Hi Jayband.
Is there a switch/toggle/something on the SF that selects the ST input? If so, maybe you forgot to use it.
Sometimes it's the simple things. I spent 26 years in fiber optics. A spec of dust invisible to the naked eye can easily block the laser.

Have you tried blowing the connector tip and port with compressed clean air? Never tilt the can! The propellant can coat the connector.

Douse a good quality q-tip with 90% or higher isopropyl alcohol and gently roll it from one side of the tip of the connector, up over the tip and down the other side. Then blow with clean compressed air. The type used for cleaning cameras.

If this doesn't work do you have another piece of gear to verify the fiber cable is working?

Please report back.
Hi 0thd,

I am suspecting that as well, here is the issue, the ST has a twisted notch to secure the cable to the ST jack in the player. If I don't secure it and yank the cable a little bit. I can heard sound!! I have other ST cables such as audio specific or data specific (for networking usage). My data cable will not work period. But the same cable will work on my Wadia 860 all the way plugged in and secured it. I will try to use duster gas to see if I get better results. Just hope I don't have a faulty ST jack, sending the unit back and forth to Wadia is pain the ass and not counting the days w/o music.....
My debug tends to make me lean forward to believe the unit has a fault ST jack:

As a matter fact, I tried the entire night and this morning, I finally
can hear audio under the following circumstances:

1) Can't secure twisted the ST cable into the 581, I have to pull the
cable out a little bit and after few tries, it's okay
2) Use a different cable (brand new) and result is the same (as a
matter fact I have 2 more ST cables, one will work and one will not
work whatsoever)
3) Using all the ST cables that I have and hook up to my older Wadia
860, no problem whatsoever with cable going in all the way
4) I make sure I use duster gas to blow out any dust in the Wadia 581
ST jack and clean all the cable with iso alcohol.