Apple MacBook Pro 15" 2016
 
	OSX High Sierra
 
	Logic Pro X 10.4.1
 
	Helix Edit 2.5.2
 
	Helix Firmware 2.5.4
 
	 
 
	We had a problem with our Helix when all of a sudden it would crash when connected into a Logic Session.  We discovered that it was tied to Logic's Control Surfaces when, in Logic, we selected "Logic Pro X-->Control Surfaces-->Bypass All Control Surfaces".  This would allow the Helix to connect to the computer without crashing, but be unusable in Logic.  We then found a Logic Pro forum post referencing how to reset the control surfaces preference.  To do this, we Quit Logic.  We went to "User Library (Finder-->Go-->[Hold Alt/Option] Library)-->Preferences" and deleted the file "com.apple.logic.pro.cs"
 
	 
 
	When we restarted Logic and connected the HELIX, everything was working again!  Hope this helps others with our problem.