i've got noisy neighbours here also. the woman sing karoake every afternoon for 6hrs. i called npp but they say they only handle cases after 10.30pm & advise me to go to hdb. i call hdb & was refer to a officer in charge of complains for my block. he's very responsible even make a trip here to know more details. he also sugguest not to confront the person directly let them handle the case. well now seldom hear them sing, even if they sing they didn't on their systems too loud.