Since rhodium is indeed a fairly poor conductor, my assumption is that it is used to plate silver so as to prevent the dulled appearance of silver oxide...EXACTLY like cheap gold plating is used on myriad copper products to control oxidation. The latter's "bling" has rationale in that copper oxide is NASTY...not conductive at all. But silver oxide IS conductive, so plating it with an inferior conductor like rhodium for "bling" is a decidedly bad idea.
OTOH i cannot comment on rhodium's "sound", as the plating is so thin, and its purpose silly, that I completely avoid it. Benign silver oxide needs to be wiped off only perhaps when you pull out grandma's cutlery for company!