I have an after-market system set up with a 15in Kicker Solo-Baric (L7), hooked up to a kenwood amp. When i have the music on, it will play the volume i feed it from the standard deck of a year 2000 lexus rx 300. However, when i turn off the music (not low volume, but completely off) the sub plays as loud as it possibly can at a low frequency. In order to keep it quite, i have to turn the music off and keep the volume at the lowest possible. Anyone know the reason/solution?