解像度やフレームレートなどの設定を変更したあと，Black Calibrationを行わなかった場合に発生する現象となります。マニュアルの指示に従いBlack Calibrationを行い，改めて撮影した映像をご確認ください。
User Manual for Software v0.3.1(9ページに解説があります)
https://www.krontech.ca/wp-content/uploads/2019/04/Chronos-1.4-Beta-0.3.1-User-Manual-rev5.pdf
Can you confirm if you are performing a Black Calibration after changing
the resolution, frame rate, or the shutter speed? The blue line usually
occurs when there is a change of frame rate and Black Calibration is not
performed. It is always recommended to wait for 15 minutes after the camera
is turned on to let the system reach its normal operating temperature
before performing a black calibration.