Noise when going over small road irregularities

I know these types of things are hard to detect from a thread, but maybe you guy's can give me a place to start looking.

Last year I noticed a weird noise when going over any type of bump in the road. It sounds like it is coming from the trans area. I originally thought it was the parking break cable rubbing the drive shaft, but that is not the case. I have the car lowered and was wondering if that has caused some sort of mis-alingment with the rear end/driveshaft.

Could body flex also be a problem?

By process of elimination, hopefully I can figure this out.

The crossmember bushings are all new. I did a clutch job 2 October's ago. The problem started then. I had to replace that clutch this spring, (long story), and the noise is still there.

The tranny seems to move around more than I remember when hitting any bumps in the road. I will replace that mount soon.

I will have to check all rear end bushings.