Recorder: Jacqui used to use raw, not boiled, linseed oil on her recorders or sometimes neatsfoot oil - rather to the horror of Brian Blood at Dolmetsch, but the slightly heavier oil did seem to give a slightly heavier sound.

Whistle: in theory (I have not tried it) it should be possible to shrink the metal tube out of the plastic block by using plumber's freezing spray on the metal tube. I have a friend who blutacks and he says it improves tone but has not mentioned pitch to me.