Audio Systems: engine running tickin sound in fm-cd crackels, pioneer deh, deh p6900ub

Question
instaled in line pyrimid noise filter good to 35 amps,pioneer deh-p6900ub reciever-cd player in my 1978 corvette.I have a 350 engine with a 50,000 volt coil and extreem output modual.The unit plays fine in radio and cd mode with engine off.The problem was worst before i installed the noise filter, but I get a 1 second interval tick with engine on and the cd player breaks up and crackels. should i replace the alternator and battery?

Answer
you need a coil engine filter this mounts in the coil or distributor
also need to find good geounds for the radio or amplifier if you have one
or you can run the ground to the battery

and get rid off that pyramid filter that is the worse filter available