Tunesmith, if you want to mess up your Spanish, listen to the online "Catalunya Musica," broadcasting in Catalan. I listen to their classical broadcasts quite often, since they cover early music recordings pretty well.
http:/www.carmusica.cat/index_cm.htm

Spaniards are used to the soft c sound; so many tourists and now Latin Americans visit.
In Mexico the 'th' is associated with 'gay' jokes.