I had a similar issue with FMQ using my HV Sapphire. Took me almost a year of frustration and hair-pulling, finally realized I actually had an issue with the BOBBIN! The dealer fixed that in about 30 seconds (repair guys are such show offs! LOVE IT!) and I've had no more issues with thread breakage. I do make sure I change my needles regularly and I use a 90 for actual quilting. Recently purchased "super sharp" skinny needles to make my piecing lines straighter, but I wouldn't use that for quilting!
Might be worth having the technician where you purchased the machine look at it. And if any burrs are catching thread, they can fix that and help you prevent more!
Good luck. Don't give up, the chase is worth what you'll catch! SATISFACTION for a job WELL DONE!