My DDJ-SX3 crashes after about 2 hours of use everytime.

I just purchased a DDJ-SX3 less than a month ago and it crashes about every 2-2.5 hours of use during my sets. It happened to me twice yesterday. Everything will be working fine and then all of a sudden the power shuts off and turns back on or the controller for some reason disconnects from my Macbook Pro. Both times it happened, it occurred about 2 to 2.5 hours into my set I noticed while I'm DJing.

That being said, I used the controller for two weddings this past weekend also but only actually DJed (live mixing) for about 1.5-2 hours at most. The rest of the time I was just playing background music directly from my laptop using Spotify on channel 4 of the controller, not actually DJing/mixing with MP3 files using the jog wheels and it worked fine. So for the wedding, the controller was powered on for about 4 hours or more and it did not crash, however I only used it for actual DJing and mixing for about 2 hours at most. It seems like after the 2 hours mark it crashes. My macbook pro is a 2018 model with touch bar and using High Sierra using Serato DJ Pro version 2.10. The controller I just purchased less than a month ago and it shows a manufacturing date of December 2018. There is also a black dot sticker next to the bar code. Is that black dot supposed to be a sticker or is it actually supposed to be printed on the box?  

Side note:  This is my 5th DDJ-SX3 I've purchased in less than 2 years.  I purchased 4 of them when they first hit the market all 3 out of the 4 were defective.  I sent them back for the free inspection and repair and got them back however they were all still not working properly after the inspection so I had to return them all back to my dealer.  I waited on purpose to buy this one I have now thinking that maybe by now the bugs and mechanical issues should be resolved.  It looks like I was wrong.