4 cylinder squeaky/chirpy?

I have a 5 speed 4 cyl Tacoma. 60k miles. When I am casually accelerating from a stop, I am letting the clutch out as I press the gas. As the clutch is let out, and the truck is at low rpms (idle speed or maybe alittle higher) I get a squeaky/chirpy sound from under the hood. As the rpms get to normal levels the sound is gone. Also, when I go over slight bumps in the road I get the same squeaky/chirpy sound. Even makes the sound if I coast (rolling in neutral - engine speed at idle) over slight bumps in the road. To my ears it sounds like something with the belt, but I checked my belt and it appeared fine. Also this squeaky sound does not happen when the motor is cold.

Any ideas? I hate to take it to the dealer to diagnose. Figured someone here might have an idea.

 

I think you and I have the same problem...

 

https://www.tacomaworld.com/threads/squeal-when-engine-is-under-load.370819/

 

I just had my catalytic converter replaced per the recent service campaign for the 2tr-Fe. After they replaced the cat, I no longer hear this noise. Hope this helps anyone out there experiencing anything similar.