A couple of things come to mind.

1.if your 5K are 18 bit and your G68 is putting out a higher rate, would cause a no sound issue.

2. Check your display to see if you are getting a signal lock.

M2.0>ROON: C15/DSP6K
C2.2>ROON: ALLO DIGIONE/DSP5K+D2500x2
W2.2>ROON: C10/DSP33+D2500
R2.0>ROON R: MiniDSP SHD>SCHIIT Freya+(Forkbeard)>3eAudio A7 Mono>>>Apogee Scintilla

Projects. ROON streamer with serial RS232 volume control