Recently this overlay keeps appearing on top of my locked screen. I have to swipe it to get to the locked screen with my password. This coincided more or less with when I downloaded some converted files from YouTube via video mp3. I've also noticed a few little things not work as they should like the download button not initially working on a film app I have. I'm worried this is malware but even if it isn't the overlay is annoying and I want to get rid of it. I've searched previous forums - I can't identify this particular overlay (see screenshot) or find any apps that it could be. The downloads list on my file comes up with nothing either. Help please! Thanks!