In Sonar it is called the "Slide" function. Set your midi ticks per quarter note to its highest resolution, now select the audio clip you want to move and then "slide" and move it backwards by "tick". To move backwards use negative numbers.
Try about 10 ticks at a time. I believe you can also slide by # of samples, but I always found ticks to be just a effective.
If moving the whole clip doesn't work then split the clip at the first closest silence and when you get it sounding right, select all of the cut clips in the track and merge them back together.