[CA11] EV-1/ACU 200/P70R - worked fine last season, now won't hold heading

[esveden]

I installed a new ACU 200 w/EV-1 and P70R, connected with new Garmin 7610 XSV with 18xhd radar on my 2004 28' Scout 280 Abaco last year, and it worked flawlessly all last summer. I launched my boat last weekend, and everything works, but the AP won't hold heading. At first, it held heading ok at headway speed, but once I got up on plane, it oscillated back and forth, getting worse if I didn't hit standby. Now it won't hold heading at all, at any speed. I tried re calibrating, went through the setup process again, and it's not getting any better. I did have to add a little steering fluid when I first launched, but seems like the steering is tight now with very little play, so not sure if that is causing any issues or not.

Hoping this is something simple, as again, it worked perfectly last year, and I haven't made any changes that I'd think would impact the AP from working properly.

Thanks in advance for any suggestions.