Vision Starboard Electric Winch

[Sunharvester]

Winch loses torque as load increases on jib sheet  A lot. To point where it grinds to a halt with more sheet left to pull.  The angle from the block to the winch seems wrong and might be part of the problem. Has anyone else had this issue?  Trying to figure out where to start. Batteries relatively new.  Rest of winches work without a problem.