Oh, yes. I should have known.
3 seconds sound clip from The New Adventures of Winnie the Pooh - Pooh Skies (S3E5).
You can hear this line at 00:01:53.320 in the Blu-ray version of the TV Series.
Quote context
[...]
- Rock-a-bye, baby, on the treetop, when the wind blows the cradle will rock. (2)
- And that one looks like a...
- It is, if I'm not mistaken, a honey pot.
- Silly old bear. You think all the clouds look like honey pots.
- Not that one. It looks like a bee.
- Where exactly do all these clouds come from?
- Well, they come from a cloud machine, of course.
- Oh, yes. I should have known.
- The cloud machine can make anything. See? There's a pirate ship.
- And that one looks like a dragon. Doesn't it, Pooh?
- The one carrying the honey pot?
- It seems all this cloud watching has made me rather hungry.
- Perhaps we should stop, for a small smackerel of something sweet.
[...]