1996 break noise

I have a 1996 Odyssey. The 96 models have 4 wheeel disk. I have replaced the breakes about 5 times in the 123,000 miles. The last time I changed the pads and rotors, I have noise. The breaks squeel when no pressure is on the breaks. The back left breaks are making most of the noise. I went to a local auto store (murrays) and used their rotors and morris pads. I am thinking the parts are the cause. The breaks work fine and I have driven the car 3,000 miles with the squeel. The only other problem I can think of is the caliper,but the rotors turn freely. Any thoughts?

Thanks
Owen

Probably due to the aftermarket pads. They are usually harder than Hondas and make alot of noise.