Like people in this thread already have mentioned - do check your track's mono compatibility. Whenever I make a sound in Sylenth1 I tend to crank the "STEREO" knob up too much. I use bx_solo to isolate the mono signal.
Also, in general, use a 100% wet send buss for reverbs and delays. This will help you create a more cohesive and definite "room" for your track. So, don't max out your CPU by having +10 single reverbs from the VSTs working alongside eachother. Unless it's for some crazy sound design insert of course.