Ok I need a waterproof (for a boat) xm radio to be connected by aux in. Any recommendations?

I use this waterproof boombox with my Pioneer Inno. It can also be used with an Audiovox XPress or Delphi RoadyXT,

http://www.walmart.com/catalog/product. ... id=4756581

Visit http://www.cyclegadgets.com/ and look under Satellite Radio They have various rain covers for motorcycle use that would most likely work for you.