I would suggest an experiment. In theory,running your laptop off of its internal battery should give you the lowest noise on the digital supply rails and the the ground plane. I would compare this operational condition to operating the laptop from the power supply which is plugged into the wall. This should be a comparison of the best case, operating off the internal battery vs worst case,operating off the switching power supply plugged into the unclean power from the wall receptacle. If you can't hear a difference between these two operating conditions,then you don't not have a problem to solve. It would probably be a good idea to run your laptop on its battery for critical listening and the rest of the time from a separate power conditioner to avoid further contamination of the rest of your system. I would not plug it into your re-generator or conditioner that supplies the rest of your system,unless of course that when you do this you can't hear any difference one way or another.
Scotty
