Your dealer is incorrect. If you want to check out some very affordable conditioning, order a Quantum Electroclear for $40. It is a serious bang for the buck and and can be used with either you digital front end or integrated and can also be used in conjunction with much more expensive line conditioning very effectively (I use two in my system along with more expensive conditioning). The electroclears are VERY effective. Your first step, though, if you have not already taken it, is a high quality receptacle. I'd probably do power cords next and line conditioning after that.