blower fan noise on 2006 Toyota Corolla

the blower under the dash has started making a buzzing noise especially on max blow. i don't think anything fell in the vents as we have been on vacation and the noise started when we got back. if it helps, it's been very hot here 95-100.

Asked by for the 2006 Toyota Corolla
Change the cabin air filter as it might have debris that is clogging the fan motor
i got a new filter today after posting this. the original filter was installed upside down (arrow pointing down)causing it to sag into the fan. it was also very dirty (my fault).
Problem fixed.