Please note that a problem of Czech abc can be hidden in the name Kadan.
The name of town in west Bohemia is Kadaň. (code Win1250).(There is a small hook above "n". It marks soft pronunciation of n. It is difficult to do for English speaking people (with the hot potatoe in their mouth) but: try to say "n" using of a middle of your tangue and don´t touch anything with the end of it.