OP/geof3 - I use a Ref3 into a Threshold S300 II, which is fairly low gain, but I've never ever, even with my old amp which had much higher gain, heard any kind of 'chime'. I've even just 'thumped' on the top cover to cause some vibration, and, silence, even with the volume at 50, which is around my normal listening position (range from 40→60).
When you say you hear a click of a relay when you turn the volume from 0 up; that's another thing that absolutely doesn't happen on my Ref3. Going from zero up, it's silent, completely, even with my ear next to it, there's nothing. Relay operation can only be heard when changing sources, never from Vol-0 up/down or anything in between, so if your makes a relay clicking sound when going off of zero, then I would do as suggested and send it to ARC for repair
And, geof3, the Ref 3 absolutely does not have a variable gain setting, as you say, either on the remote or the unit itself.