My dealer says the cars all do it.Independent mechanic recommended using an aftermarket belt instead of Toyota since the Toyota belts seem to get noisy at about the mileage you mention, colt.
Belt's probably fine and can be easily inspected. Problem is normally just annoying.
If you are on warranty, dealer may change it free. They did for me and it stayed quiet for about 2 years.
Thanks for the info,Bob.
I may just take a shot with the dealer.
After warranty I may go with a Gatorback belt if one is available if needed.