There are already many posts about this, you may have done something to the antenna if you took it apart recently. my first one did this after about three days, so I just took it back and exchanged it. The Radio Shack paople are pretty good abou this sort of thing.
o.k i got it figured out . the last i did some modifications on my car the wire that connects to the antenna came loose. i soldered it back and now it all fine. just to let you know. later.
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