i bought an aftermarket head unit for my 94 ford probe. i go to install it and i see that i have a premium sound system installed. after i spliced the power wires and stereo wires together, i turn it on to see if it works. it turns on perfectly, but there is no audio coming out of any speakers. there is a set of wires that is not hooked up to anything, and also there is a single wire that is also not hooked up to anything. can anybody help me?????