You need to READ retrofit basics ...they are on the first page on this forum.
Most answers are posted there.
You can connect CD changer but IMHO is pointless while you have 2 SD slots which gives you over 1200 songs, or you can connect any other MP3 / media player
Most answers are posted there.
You can connect CD changer but IMHO is pointless while you have 2 SD slots which gives you over 1200 songs, or you can connect any other MP3 / media player