I am sorry I cant help you with the Clairion stuff or the M.B. quart. But as far as a good mp3 player, there I can help...
I carry Jvc and Pionier and both have a mp3 player just depends on the options as to the cost.
e-mail me if you have any other questions.
p.s. Forest or Audiofn sould be able to help you on the other problem.