Nes Advantage with hairline crack

Hi,
I noticed not too long ago that my beloved Nes Advantage joystick is developing a hairline crack on one of the sides. In inspecting it, it doesn't look like a scratch as at one end the plastic around the crack looks discolored and brittle. As its on the side, I guess it isn't hurting anything at the moment, but it is a little disturbing! Would anyone care to offer any suggestions for preventative maintence, or would it be best to leave well enough alone?

(see attached somewhat crappy cell phone picture of said crack)


Thanks!