Throttle Drops Down to 0% while Mode Changing

I’m working on an turbine engine project with PX4. While I was starting the engine with stabilized mode engine is working good but when I wanted to change mode to mission throttle value dropped down to 0 for 0.3sec and after that it increased to the value which I specified in RWTO parameters. In this transition period turbine engine is stopping. In electrical or IC engines this is not a problem but turbine engines are more sensitive.

First I increased the ramp up time from RWTO parameters but it didn’t work. After that I decreased it and it worked for a while. The transition was perfect. A day later I tried again with the same settings and didn’t work again. How can I fix this problem. Is there anybody to help?

In the same time while plane was on the ground the flight controller suddenly doing disarmed and armed for less then a one second. Maybe these problem is also connected to the first one.