Hello, I purchased a bluetooth receiver board to install into my old car. I am using a aux cable that I previously wired in. When I play music through the board the sound is very quiet. I then bought one of your mini amplifiers (30w+30w) to see if this would fix the issue, but it does not. The music is louder but the quality is no good. Is the blue tooth board supposed to transmit a line level output? I would like to know what the fix is for this or if there is another solution. I just want to bluetooth connectivity for the original head unit of my car.