Shrieking! Help my ears please!

[Spixie33]

I have a 15 month old who likes to shriek. It is usually very random that she will just do it while watching the other kids or while standing around.
I think she is doing it to hear her own voice and try it out.
Thankfully she does it for only a few minutes at a time once a day or twice a day.

I alternate approaches....I start by firmly saying "No. Stop. That hurts our ears" and give her a serious look so she sees it is not funny.

If that doesn't work then I try and ignore it and see if she loses interest when no one engages.

I find one or the other usually works. Sometimes she likes getting me to address her so it gets worse and then I switch to method 2 and sometimes method 1 works.

The worst is when my three year old DCK laugh and find it funny which then makes the shrieks go on and on and i have to give a scowl and a scolding to each of the kids for encouraging her