Try putting some of the black specks on a piece of white tissue & wetting them. If they go red then they are flea faeces. It's because of the blood they are sucking being passed out.
Frontline works by being a contraceptive for fleas to prevent them multiplying, rather than killing them outright. So any new ones they pick up outside the house will still be live. Mine sometimes bring them in from the grass in the garden if there have been hedgehogs around. |