For mine it turned out to be low oil. My oil tank had about 1/3 left in it which is enough for about 5 more trips out for me and looked fine.
Turned out when I was cruising along the engine was level and then when I went WOT the boat rises up and would think that I had low oil. It would lower the limiter and would then decrease the lower the oil is.
Jizm made a comment about the "get you home mode" so I thought id just fill up the tank to see if it made a difference. Went out and she was fine !
Note to self, have more than 1/3 oil in the tank
Big thanks to Jizm or I would still be trying to fignure out what it could be....