I just bought two Aura Pro Bass Shakers, as well as a Dayton SA 70W Subwoofer amplifer from Parts Express. When I hooked one the bass shakers up to test it out, there was no vibration or shaking! I used a Y-splitter to connect RCA cables from my receiver to my subwoofer and the amplifer. I then used speaker wire from the left speaker out of the amplifer to connect with the bass shaker. I've tried just about everything (switched from left to right speaker out, adjusted the volume and frequency knobs on the amp, but still nothing! Can anyone here help with this problem?