Logic Pro X Stereo output fader moving erractically

#1
This is weird. At the end of my project, about last 2 bars the sound breaks up and the fader moves up and erractically. I have automation in project but seems to work ok. Also my CPU is spiking and audio indicates audio even when no audio us playing. Could it be a bug in software? Any guidance will gratefully receive. Apple MacBook pro 15 " 2015 model.
 
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