Hello Kat,
You are totally right. I had the same problem with a colleague of mine in the office. He used to climb up the stairs loudly whispering and continue in the entire office. Finally I lost my patience and shouted at him and we came to face to face. After a while we all calmed down and apologised to each other, in the end he doesn’t whistle anymore. Mine can’t be the best solution but I do agree with you.