I do not think there is a difference between the CDR220, CDR-220, and CD-220 (I'm not even sure that CD-220 is even a correct name for the Becker), they're just different names.
Also, when you get this static, are you listening to the radio, a cd (head unit), or a cd (cd changer), or another input like an iPod?
You could have a loose connection if it is happening from a cd changer of other input.
If it from a cd in the head unit it would be the cd, or the stereo, and if it is the radio it could be a normal static radio frequency.
Also, cell phones are now to cause some problems, so if you leave your cell phone near the head unit, put it in the center console and see if that helps.
Hope this helps!