i have a sony xplod cdx-gt10w. now, when i adjust my EQs i foind that when i turn the low down it affects my speakers and my sub. also when i turn down my sub output it affects my speakers and sub. i only have one pre amp output. now i have two amps. one for my sub and, one for my speakers. i run rcas from the deck to the sub amp then to the speaker amp. could this be a problem or, is it the deck.