Just recently noticed that the right side of my S6 was low especially the right rear and occurs consistently when siting overnight. Once started the car leveled up quickly. I have no suspension codes on the dash and the same when I looked in VCDS . I tried putting the air suspension in Tire Change Mode and the car did not sag overnight. Seems to me this pointing to the air suspension solenoid block going bad?? Figured if it was either the air spring or front air strut failing it would have sagged even in tire change mode.