I am not sure why you use a screensaver, maybe because it's pretty? Screensavers don't save your monitor. I just turn off my monitor if I'm going to be away from my computer for any time. Screensavers were invented/created when years ago burn in was a problem, that is not the case now days.

However, for whatever reason you use your screensaver, have you ran a spyware check on your system lately?