Play using sound of selected staff

This request is about what sound it uses when I play on a MIDI keyboard. This is when I'm just playing to experiment with ideas, not in note entry mode. If I select a measure of one staff, then it plays using that staff's sound. But it only works if the current selection is a whole measure. If I instead select anything else, it ignores the selection and uses the sound of the top staff. I suggest that if any score element is selected, it should use the sound of the associated staff. If I want to experiment with ideas for the cello part, I should be able to just click on the cello staff and start playing. I shouldn't have to be careful about exactly what I'm clicking on. Right now I have to be very careful about it, because if the click selects anything other than a complete measure, I get the sound of whatever is the top staff instead.