Whistling Nose Sound When Sniffing

For about a week or two my kitty has been making whistling sounds when he is sniffing. It doesn't happen when he's just breathing of sniffing gently but when he takes a good whiff I'm hearing a whistling sound from the area of the nose. Is this normal? Could he have something stuck in there?

Geez...I haven't had a cat in 30 years and I feel like a new mother again encountering lots of new things.

Is he eating? Drinking? Using the litter box? Playing? Pretty normal? Then I wouldn't worry.

If however, he is lethargic, can't play well or for a long time, not eating or drinking right.....then I would say that a trip to the vet's is in order.

Yup, all other behaviors are normal for him. Thanks.

Sometimes you can hear the odd whistling sound coming from Sophie when she's asleep, and when i took her for her yearly checkup i mentioned it, but they examined her it was nothing to worry about