Another good suggestion too.Yes, please torque your wheel lug nuts to the required value for sure! I check mine occasionally - definitely do it yourself after each wheel rotation (I do mine at the place I buy/install the tires from), since I do not trust them to keep their torque wrenches accurate, calibrated, undropped, etc.
BTW, I bought my torque wrench at Sears rather than an online store, because they will calibrate the torque wrench periodically for free ... reminds me, I need to get mine done ...
Z
I don't know if this could be the same sound you are experiencing or not, but definitely check it out for sure if you have not yet. For me, it was a simple fix, yet a potentially dangerous and stupid thing to have happen.