Thanks for the input. Is your advice to keep the volume below 87 because that is where the analogue gain kicks in?

iMac -> Sonos -> Empirical Audio reclocker -> G68 (modded) -> Pass Labs XA30.5 amp -> Focal 1027be speakers + JL Audio F113 sub. Pioneer Elite PRO 151FD 60" display.

G68 mods... Custom power supply, Audiocom Superclock 4, Rubycon capacitors, WBT Nextgen connectors, ultra low noise op amps, analog output buffer, DSPC c00044, Revelation One filter.