New brake pads and rotors but brakes still squealing.

Approximately 4 weeks ago, I replaced the front pads and rotors on my 09 Aveo5 LT. The job went smoothly and the car stops on a dime. However, within a week I was getting a squeal every time I stepped on the brakes. After another week of the noise getting progressively worse, I took everything apart and cleaned the calipers and rotors as well as making sure the pads were seated properly. Once reassembled, the noise diminished but never really went away completely and now it's getting louder again. What am I missing? And, more importantly, how do I correct this issue?

Thanks in advance for your assistance.

Did you change the brake hardware? Did you grease the hardware? What kind of pads are you using (ceramic, semi-metallic, etc)?

I also changed the metal 'clips' which sit at the top and bottom of the calipers. I greased the pins that insert into the calipers as well. I installed ceramic pads.

I don't have any noise coming from my brakes, and I did the full calipers (passenger side was seized), rotors, and pads (semi-metallic) last September.
Car stops on a dime, now.

I would like to hear (ha, see what I did there) what the problem turns out being.
I considered the ceramic pads, but money constraints had me go semi-metallic.