Stereo Tool

I got RDS and stereo signal to work well on a cheap mono fm trasnmitter using a single core PC and N-Audio Revolution 7.1 sound card {and onboard audio}. However, this transmitter doesn't allow me to change to the frequency I want. I do have a FM Stereo transmitter that works well. Except when I try to send RDS and select Pre-emphasis in stereo tools, I can hear it already has pre-emphasis and RDS does not work. Is there a way to remove pre-emphasis on these transmitters? If so, what am I looking for?

This transmitter looks similar the cheaper belkin kind.

gebruik je toevallig een chinees tiptoets zendertje ?
met een vermogen uit een lopend van 5 tot 15W