This board seems underpopulated (tho how many people own a Lyra?!?), so hope this response reaches its asker – I have a similar ‘issue’ with voice #6 & its relationship with that pair’s MOD control, but have long since embraced this as both a ‘feature’ and a quirk; as long as the device doesn’t fail (cos who could repair it?), for me it adds a functional indeterminacy to the device as a whole, and have embraced this, esp live.
It did worry me initially, but has remained for some years at least predictable in its unpredictability!