Unstable elevator in autopilot

[hudkinsnoah]

I am looking at adding the Global5000 aircraft to my program and integrating it with autopilot. I have added several aircraft in the past and never had this issue that I am experiencing. When I give my autopilot a command to level, the pitch is very instable and will start to pitch up and down rapidly. The pitch is graphed as follows:

The instability starts small at first but starts to get worse and worse.

Here is another example of the issue with the pitch:

If there is any more information needed, let me know and I can provide that. Thank you in advance!

[hudkinsnoah]

After evaluating this more, I think that it has to do with my speed and trying to keep steady at top speed. When I lower the speed, I am getting a smooth and consistent ride so this was a user error :)