Would you tell your teen you can hear him ...doing what teen boys do....and could he please do it quieter?

[weebleswobble]

I've posted before about walking in on him and learning to knock before entering his room.

Now the problem is I can hear him in my kitchen because his bedroom's above. So, as I prepare dinner/wash up/generally potter, I hear him wanking.

I know it happens, and they all do it, but I really don't want to hear it.

Tactful approach?

DW's two brothers shared a (quite small) room when they were growing up. I mean, HOW did they do it?? Because all boys do, obviously.