simulate this circuit – Schematic created using CircuitLab
Currently facing some issues with noise/stability. When a multimeter is connected across Vout and Vref, there is a effectively no noise/oscillation i.e Multimeter reads 0.0012 mV r.m.s. However when an oscilloscope is connected to it (simultaneously with the Multimeter) the noise level rises to 1.8mV AC. I understand this is negligible however this is part of a current measurement circuitry with a T.F of 40mV/A hence its important to keep this reading as low as possible. The reference voltage is used to provide reference to the other subcircuits within the whole system. This is what I have tried so far, a snubber ciruit; series RC from Node B to ground of 10nF and 100ohm resistor. ALso tried a snubber between nodes A and B. Tried playing about with the compensating resistor R1 but increasing this seemed to made it worse. L1 and L2 are Ferrites respectively. I have tried shorting these out and also playing about with the resistance still no help. Anyone have any other ideas.
UPDATE: I have just found that its in fact the ground connection of the scope is what's causing the issue. just attaching the ground clip on the vref point or Vout upsets it and raises noise to 1mV AC
Regards.