He’s begun the recorder metaphor already.
To play the recorder, one must cover a hole, to stop the wind. The wind here – feels as if it is the air, the animating force, the inspiration and animation of the self (link to this line in genius) Or I think, too, of the wind in Chinese medicine – there must be some equation with the humors. . .what is in windy humor?
Or is it a fart joke?
I mean – the ESSENCE of the line is obviously, “Why are you being such a pain in the ass?”
But – the layers of metaphor and meaning are complex.
I picture it literally, like Guildenstern is squeezing Hamlet, a bit like a recorder, but also a bagpipe, trying to get him to make the sound he wants to hear. He blows into him, hoping to get music – but Hamlet’s not willing to be played.