Hi Everyone, im having a little problem

I installed a Pioneer head unit (DEH-P3800MP) into my friends 2000 neon last night. It works good but the radio doesnt really pick up signal all that well although the antenna cable is in correctly. The car had an old cd changer controlled by an FM modulator which is still installed...could this be an issue?

Also he mentioned that his alarm went off this morning fo no apparent reason...is there a tie to the head unit?

Thanks