Malfunctioning autopilot

[Tamaroak14]

We have a Raymarine SmartPilot, purchased new in 2006, hooked to an ST7001 controller. It now goes nuts more and more frequently, steering off to either port or starboard while maintaining the same heading number when the ST7001 is set on auto. When I go to standby to be able to steer, the numbers clock around to match the circling heading of the little boat on the chart plotter. When I'm on standby the numbers and little boat spin around, sometimes quickly, sometimes slowly, sometimes clockwise, sometimes counterclockwise.. Sometimes it settles back down to be useable again. All metal and magnetic materials are clear of the fluxgate compass.

Is the fluxgate compass bad? What do I buy as a replacement?

I'd like to check the connections of those tiny wires that go into the course computer, but can't figure out how those little "T" things work and don't want to unconnect something. How does one fasten and unfasten the compass wires to the brain box thing that says "SmartPilot."

Ideas?

Thanks, jeff janacek