Noisy Cable/DVR Box

Good morning,

      Yesterday we received a "new" cable/DVR box my wife and I installed it with little or no issues.  This morning when we got up my wife stated, "Boy that cable box is really noisy !", I went into our living room and could hear a fan type motor running constantly.  We rplaced the other box which we had for 3.5 yeras because we were having issues with the DVR function.  I see from other postings that this a common issue to "older" boxes.  The label on the box reads Arris Group,Inc., Model AX013ANM.  Please advise what can be done.

Thank you,

Bob