What I learn from this : Only trust yourself ! :d/

I am having a similar problem integrating my Buffalo III with the Opus USB receiver in SPDIF mode. I have always used the USB receiver in I2S mode because I could never get the SPIDF to work. Recently, I've wanted to integrate coaxial and toslink into the buffalo III which prompted me to pick up the 4:1 Mux board and input selector. In attempts to switch the USB receiver to SPIDF via the jumper and connect D0 to D1 (Buffalo) and GND to GND (Buffalo) I never get a lock on the signal. The mute is always visible. My configuration on the buffalo is stereo output. None of input jumpers are shorted on the DAC. I have the SPDIF auto detect set to ON (dip switch 2 pin 5) and oversampling filter is set to ON (dip switch 2 pin 4). Just for kicks and giggles, I installed the 4:1 Mux and piped a coaxial SPIDF signal into the board with the input selector switch set to the right channel and I did get the mute signal to go away, but the lock never became lite. I would like to try and get the USB receiver working, as I know that the module works with I2s.

Any help is appreciated. I don't know what else to do.

Currently, no, the coaxial and toslink sources don't fully lock. The lock light blinks weakly, and the mute light is off. I am going to try and shorten the ribbon cable to the BIII to see if that has any effect. If I just have the USB receiver hooked to the D0 on the BIII the mute light is fully lit. I measured the output of the USB dac when playing music and signal reads 0.7pp with a 1.5 bias, is this correct?

Thanks Brian