Ringing From 360/12 Tailpiece

[Tommy]

I have had my 360/12 for fifteen years but it is just now that I am noticing a very loud metallic ringing from the strings below the bridge to the tailpiece. Hit a chord hard, and you get this nasty ringing. I know it is the strings before the tailpiece because I can dampen them with a polishing cloth stuffed under the strings to get rid of this sound.

Must I play my beautiful Ric 360/12 with a polishing cloth stuffed under the strings?
How can I get rid of that ringing (it is loud in an amp)?
Do yours ring like mine?
What causes it?

Thanks.

[byu]

There are several ways of damping the strings behind the bridge. The best are: using rubber grommets, which you can get at Radio Shack, between the strings (popular with mandolin players). Or, a less visible, esthetically pleasing solution, is to wedge a strip of felt between the strings and the portion of the R tailpiece that extends out over the strings.

[Tommy]

I just tried your wedging a piece of felt between the 'R' tailpiece and the strings advice. Works fine. Oh, what a 27 cent piece of felt can do to help out a two thousand dollar guitar.
Thanks so much.