Chosen Solution
The plug does not fit snugly into the port and it is hard to get it to retain a connection. A new adapter is loose as well. From research it looks like to replace it on this model requires soldering? Is there anything else I can do short of paying someone to solder in a new one? Thanks.
@onyxeyez you are correct that the DC-IN socket is directly soldered to the motherboard. You will have to get it soldered and it might help and be less expensive, if you remove the motherboard and get it soldered by someone local.