Just a thought, and not sure if you tried this yet:

Is this through optical cable only, or does it occur in 6CH as well?

If it happens in 6CH as well, maybe switch R/L from your SACD player and see if it moves to the other side.

Did you ever check to see if your Center isn't heavy on the Left? Those are pretty big woofers on that baby. :rolleyes:
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Nert's Home Theater---
Mostly electrically driven box-shaped things (with dials and buttons) connected by wires and cables of various colors, diameters and lengths.