this is very weird. My sister just came home for a visit from school and her laptop has a constant frog croaking on it. I can't find which program is doing it but it sure as hell is annoying. Neither Ad-Aware or Norton can pick it up....any suggestions?
Really though, check the startup tab on msconfig (Start -> Run -> msconfig). Untick the boxes of any startup items that you know don't need to run, or that look suspicious. You could also check Add/Remove for unwanted apps, or... this is a stretch... do a search for the word 'frog.'
You might also post screenshots of the running processes under task manager... maybe that could reveal something.