Hi, you could add a Reviver or Steve Eyles's 'SpeakerLink to Legacy DSP cable', to convert the SpeakerLink output to SPDIF and use that to feed your G68 rather than optical.

It may boost AQ as well (I'm not a big fan of optical connections on Hi-End setups).

Regards,
Carl

861v6+ID40, HD621, 8000.2, 7200HC, 7200.2, SKYQ Silver, PS3, PDP-LX6090, QNAP TS870-Pro (8*6TB), Roon, iPadAir2.
[In Reserve] C15, MD600 (2*3TB), TwinStore RM (2*2TB)