Go back to basics
PAT the CAT you daft ****
Power Att Trim Check Att Trim.
Then after its trimmed leave the bugga alone. Take your hands off when your flying and doing something else ie radio etc.
You will be fannying around putting inputs in when the machine is quite happy flying the profile you have set it on.
Lighter grip and let the machine do its stuff. And let it stabilse don't chase airspeed, set your att and config and it WILL work. IF after a time you see a trend then alter power but not until everything settles.
MJ