1. If you have the white spring in the unit, then the cables may be loose in the same manner. This is a very light resistance spring so the weight of the machine and gravity start to compress the spring. Try switching the spring to higher resistance and see if you still have the issue.
  2. If one side is looser than the other, it is possible you pulled one side to come out of the clamp. Simply pull on the other side to set the cable again.