Interference and dodgy speakers

[systemseiko]

Put a new Blaupunkt single disc head unit in my MK 2 GTI a few weeks back and works a treat other than when playing a CD,  when the CD is played the speakers crackle as if ther is tooo much bass ,  i have resorted to turning the bass and treble down,  now for part 2,  As the world cup is upon us i have been trying to listen to Talk sport with no avail,  i can tune near perfect when the car is not running but once started i get the engine reving coming through the speakers,  i fitted a suppressor onto the output wire on the alternator thinkin that would resolve it but it is still sh!te. 
any ideas anyone as i'm fecked off with the crap noise.

[Heyho]

You don't mention if you had the same problem with the previous head unit - if you didn't, try putting the old one back in temporarily - if it's OK then your new unit is faulty - or extremely sensitive.

[systemseiko]

Sorry forgot,  both head units had the interference, although the old head unit was stonehenge material,  i have not modified the existing ISO connectors in any manner and all wiring is OE standard