Extruder Axis Buzzing when trying to find home

Title says it all. When the extruder axis tries to find the end of the axis, it just buzzes and doesn’t stop unless I purposefully induce a torque on the axis, or shut the unit down. What do I need to look for\adjust?

https://www.youtube.com/watch?v=bdHF8KCUkVY&feature=youtu.be

Thanks. Just FYI in my case it didn’t have anything to do with shipping. This happened to me after months of use.