[sfontain]

Not to state the obvious, but here are a few things you may want to check:

Your rotors could be warped but you should feel a shudder in the brake pedal if that's the case.

Ensure that your tire pressure is up to spec.

Are your wheels balanced?

Is it possible that you have a bent rim? (E.g., slide into any curbs recently?)

Question: Did this noise develop suddenly or over time?