The first thing you should do is to check for some visible damage to the adapter. If something wrong with the outer rubber coating, so that the conductor is exposed to the interior was damaged, which could lead to interference on the course and give you a cause of snoring. Loosen the knots when the cable was connected. Make sure the connection if the cable meets the requirements of the card box is still intact, which can sometimes be damaged and become a bad connection. Then you must repair the damage with tape, and then cover all exposed areas.
After that, do plug the AC adapter into the same outlet as the other equipment you are using. As most of us know, some apartments and houses have multiple phases of power that can create audio interference if mixed together, consquently, do running everything off of the same phase might get rid of the buzz.
Finally, you can protect your equipment managed by a surge protecting power strip or power conditioner if necessary. Audio and video equipment is particularly susceptible to interference caused by ground looping. Currently, power conditioners smooths the way and protect your equipment from spikes or thorns.