It would be illegal to capture audio. So that is a legitimate complaint. You could not only sue, but you could alert the police and the landlord could possibly get into trouble criminally.
If the camera is taking footage of the inside of your unit (or office, etc.), then you also have a legitimate complaint, and can indeed sue for invasion of privacy. But if the camera does not take footage from inside of your unit, then the landlord has done nothing wrong so far as the video footage is concerned (though as stated above he may have trouble regarding audio).
If I were you, I would attempt to find out about the audio, and if it appears that audio is being recorded, then I would consider retaining a local attorney to write a cease and desist letter, and then possibly sue if necessary. This can also be reported to the police.
Does that answer your question? Please let me know if you need clarification, as I am happy to continue helping you until you are satisfied. Also, please remember to provide a positive rating via the stars (and note that your positive rating is the only way that I'll get credit for helping you, so it is much appreciated!). Thank you. :)