QUESTION ABOUT TRAKTOR+DJM T1

Ok so just got my DJM T1 yesterday (02/06/2013) and everything is going fine..i have minor issue when i am DJing at home however wouldnt be minor in the club. As im mixing there are times the track will stop playing, then the waves will highligh red. time CDJs are still playing, as soon as i click a part of the song on the waves it will play again?!?! help?

2ndly....can someone point me in the direction to step by step on how to set samples to my cue buttons on lower left and right side of my mixer?

Thanks in advance!