When I bought my 318 the antenna was frozen as well, it seems like they don't do too well if they don't get used. I was able to get it fully functional with some WD40 and a lot of patience. If I remember correctly, I did actually use some extremely fine sandpaper(600+ grit, might have been 800 grit) to polish up the chrome on the antenna mast. This last issue, I was thinking I Might try a "Magic Eraser." I use them to polish the chrome on some stuff in my kitchen when it needs it, it works quite well.