latenncy

Hi guys , need some help here.. I've made a song in reason. Now I wanted to add some vocals .. So I rewire reason to sonar. And press the rec knob on an audiochannel. What happens: I hear my voice for about a second later . Not playable !! I go to the buffer slider in the audio menu and move it from side side to the other side. But the latency stays..  Also tried putting the audio file of reason in audacity and  record my voice there but the same happens ... Whart can i do about it .. I have an m-audio firewire solo soundcard which in my opinion is decent enough..  I play my microkorg through a mixing table .. Could it be that I should play it directly into my soundcard .. ? or ..???? thx alot