Hard knocking/ squeaking noise from rear suspension.... what could that be?

What is your question?

I have yet to figure out one variable that is constant when the noise happens it could be hot it could be cold in the car could be sitting for hours or just been driven him if I'm going slower if I'm going fast going straight turning it doesn't matter it's very intermittent it out sometimes there's days that it will make that noise constantly but then there's days where doesn't do that at all the only thing that I've had fixed is one side the back shock was replaced, but still not fixed. I even have recordings on my phone of the noise while I was driving I have been to two Mazda dealerships and not a single person can tell me what that noise is. What seems to make the problem better or worse? I don't know How long have you had this problem? 5 months