No reason for this to be the case, however, certain amplified (plugued-in) antennae could be equipped with a questionable quality wall-wart power supply, and one of these, close to receiver's wiring or sharing the same power circuit could cause RF interference.
I use un-amplified antennae on two of my TVs, and if anything, on the channels that do come in, they yield a better result than my digital cable box for both sound and picture.
