I have just installed the F500bt into my 01 VW Jetta. The F500bt and nd-g500 amp works with sound and everything. However when I turn the F500bt audio/video/map to "off" the factory radio has no sound. (It does turn on though) The factory radio is working normally when everything is returned to stock without the pioneer system. Any suggestions? Could it be a faulty amp?

 

Thanks!