V Vocal and Melodyne not working - crashing audio engine

Ok I have looked around everywhere it seems like and im just getting super fustrated. I cant seem to find any info on this.. I can load both Melodyne and V Vocal up on tracks but once I try to play the tracks with this on them the audio engine drops out and wont recover without me restarting sonar all together.. I normally run my buffer at around 5ms and I use the Scarlett 18i20 as my main interface.  So it will have the little icon up near the transports say audio drop out.. and then the audio engine icon will go dark, but wont come back on.. nothing. I know its not computer horse power im running a 8 core processor, soild state drives, and 64 gigs of ddr4 ram.. Audio doesnt push this computer at all, it was build for heavy video editing... and this problem has only started about a month ago and I cant figure it out... I can make changes in melodyne and then render the clip, exit sonar load it back up and it will play it fine.. 
 
DOES ANYONE HAVE A CLUE WHATS GOING ON OR WHAT I SHOULD DO? I have tried uninistalling melodyne and reinstalling it and that didnt help..