Usually pag onboard soundcard lang, may delay talaga. For now, your solution would be "ASIO4ALL". Google mo lang and download it (for free), then install it sa pc mo. Pag onboard soundcard usually WDM ang drivers e.
Puntahan mo audio settings sa Sonar (Options > Audio > Advanced, then select Asio as driver mode). Also go to the General Tab (Options > Audio > General) and select your playback and record timing master.
Of course, the best way is to get a usb or firewire audio interface. Mas safe ang pc mo. Pag onboard soundcard lang kasi minsan nakakasunog ng chips ang line in recording (lalo na pag instruments ang nirerecord mo).