Weird clicking noise from front right wheel - low speed

[Blanketnam]

Hi All

My 2011 yaris zen 3 hatchback has now started making a strange sound when driving very slowly. It almost sounds like something is rolling around in the wheel rim. It's a metallic sound.

But, I only hear it at very low speeds, like below 15kph, if I roll my window down (right hand steer, front right wheel makes the noise).
I can hear it more clearly if someone else drives and I walk next to the car.
Could it be something inside the tire? It doesn't have a puncture so I can't think that something is inside the tire.

Any help would be appreciated!