Could be that kitty is just a little shy and needs some more time to adjust...

Mum's boyfriend has a pair of Burmese who almost never Meow, but when they do, it is very low and hard to hear. They purr like jackhammers however.

Pixel has not one, but TWO meows ... most of the time it is very light and melodious, like a fairly normal DSH kitty girl. But! When she wants to, she can bring on the Meezer Meow in a big way - it's quite odd to hear two totally different sounds coming from the one kitty!