Microair M760 Transceiver picking up engine noise when over 2100 RPM

EDIT: Found the answer, VOX can be set between 1 and 42 with 1 being always on (extremely sensitive) and 42 you have to yell like a drill sergeant chewing out a private to activate intercom.

Has anyone experience with Microair M760 Transceiver picking up engine noise over the VOX intercom from the Mike? I tried playing with the VOX settings however that did not seem to do much if anything. I was able to cover the mike with my hand wrapped around it and that made the engine noise on intercom go away. Am using a new pair of David Clark headsets.