Audio doesn't play back well

I have a 1080p motion graphics project that is about 10 seconds. I have some music and a little bells transition for a move. When I play the piece, it can't play the music and the FX sound track all at once. In fact, the audio performance is incredibly slow and buggy. When I press play, it takes a couple seconds of playing for the audio to even play at all.

These are WAV files about 2.5 megs each. Nothing huge.

Hardware is full blown Mac Pro 2013 12 core with dual 700 GPs and 32 gigs of RAM.