Larsen with Ampsimulator


I am a beginner in playing and recording music with Cubase.
So i have a UR22mkII as external audio card sound, with two audio monitoring plugged on it.
I have plugged my electric guitar on the second line of the sound card. After configuring cubase and add an audio track with this second line as an inuput, I hear well my guitar with clear sound on the daw output.
The issue is coming when I add an ampsimulator as insert effect. Some configurations, espacially the one with gain and distortion creates automatically an awful larsen in output…

I use the Yamaha Steinberg USB ASIO as Audio driver.

If anybody can help, it could be very kind !