The dropdown menu links to 404 page

Hi, I downloaded the plugin and it's exactly what I was looking for. The only problem is the html extension that it directs to. 
I want it to go to http://www.brbaptistchurch.info/testsite/sermon-speaker/james-martin/
but it goes to this (which gives a 404 error page) how do i change it?
http://www.brbaptistchurch.info/testsite/?sermon_speaker=James+Martin

Thanks so much!

Josh
