Remove the:
mc3man/trusty-media/ubuntu
ffmulticonverter/stable/ubuntu
PPA's.
The developers have not given support for 20.04 Ubuntu based distros, such as Linux Lite. How to is in the Help Manual. You should also read the PPA section before adding any more in the future to avoid this again. Cheers
![Smiley :)](https://www.linuxliteos.com/forums/Smileys/MSNIcons/smiley.gif)