So after about 6,000 miles on the odometer, I started noticing knocking sound from the rear left wheel area at very low speeds. After eliminating every obvious potential reason by myself, I have decided to turn to the dealer with this as part of the 7,500mi service. They also couldn't find any obvious reason so after 2 days of investigation they decided to replace the shock to a new one and that solved the issue. The vehicle was never abused or went off-roading or anything like that, so it was simply a case of bad part from the factory.
Just sharing in case some else bumps into something similar...
Just sharing in case some else bumps into something similar...