Hi,
is it asking too much for a simple sketch?
VRef is DC and it should come from a low impedance source. (but we don´t know nothing about the source)
Thus I don´t expect any change in DC voltage. (We don´t know nothing about the load / load crrent)
Mainly the signal may be influenced by HF. (We do not see any HF source)
We also don´t know about routing, GND plane, GND currents, distances, frequencies.......
--> From all we currently know: a simple RC filter at the receiver side should work.
Klaus