Whenever I re-rack the squat bar and dip out from under bar, I get this popping/cramping sensation in my upper back about where the bar sits and just to the left of my spine. It doesn't happen when the weight is unloaded, but when I actually drop my arms. Does this happen to anyone else here? The pain is transient and not to a degree that makes me want to stop, but it is annoying and I do worry that I might damaging something. It's like the bar has pushed down some bit of tissue in my back (I'm completely ignorant of anatomy) and it needs to pop back into place. If that is what's going on, I'm not aware of it being pushed down -- only popping back. Occasionally, it will be a little sore the next day. Effect increases for work sets over warm up sets. This began when I first started squatting many months ago and disappeared. It's now been back for several weeks. Work set is currently 260#x5x3. Hope this doesn't sound as ridiculous as I think it does.