There's an intermittent noise coming from underneath my car - what is it?

I have a 2006 Kia Picanto, 58,000 miles. For the eight years I have owned it, it's has been more or less problem free. Now, after I've been going for about 10 minutes at reasonable speed, there is quite an audible noise coming from under the car, nearside. Garage have checked all bearings and can find nothing wrong. They've replaced the front brake pads, but it is still happening intermittently.
If it's not the brakes or drivetrain, might be the waterpump starting to wear out, or the timing belt tensioner.
Answered by Honest John on

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