The only reason it should sound 'hollow' is if you are hearing the live track and a delayed track at the same time. Are you sure you are only monitoring one track? Even a 10 sec delay on a single track won't make it sound hollow or robotic.
Remember to mute the track that you are recording in the software. Otherwise you are probably hearing the recorded track being mixed back into the monitor mix through the main buss along with the direct hardware monitored track and that would definately cause it to sound hollow and robotic.