How far was the fox blr...?
He did seem preoccupied but maybe he didnt hear you...?
What sort of whistle is that & what animal are you trying to mimic with it...?
Maybe trying a volume/technique/style of whistle...
Sometimes they not interested...he might have just moved into the territory from others youve shot & so be all full of himself advertising his manhood...
The man who knows everything, doesnt really know everything...he's just stopped learning...