Very violent banging when tumbling. I removed the front & back panel and "tested" the shocks and they seem intact. The spring suspension system also seems intact. There is evidence of the tub having hit both sides of the cabinet, however I don't know if the marks are from this episode or damage from a previous time when both shocks were broken and the tub gyrated enough to smash the soap dispenser. I don't want to go through that repair again!
I rotated the tub, from the back, by hand, and notice quite a loud clunking while the tub turned, I have attached a sound file of the clunking that I heard while a spun the tub. During the wash cycle, when this violent banging was first witnessed, I notice a heretofor unnoticed slight "squeak" as the tub spun...prior to the beginning of the banging.