noise within walls

hi all, we are living in this newly built building and there are tons of issues that the sponsor has yet to address, but he has dragged his feet so long we're probably just gonna give up. however, there is this major issue: noise coming from behind the master bedroom wall. even since we moved in, the noise has been on and off. we didn't think much of it, until in recent months it would go on... [more]

hi all, we are living in this newly built building and there are tons of issues that the sponsor has yet to address, but he has dragged his feet so long we're probably just gonna give up. however, there is this major issue: noise coming from behind the master bedroom wall. even since we moved in, the noise has been on and off. we didn't think much of it, until in recent months it would go on non-stop for days. so i ended up sleeping in the living room a lot of nights when the noise comes on. despite promises to figure out this problem, the sponsor has not made much inroads. here's the account. last november, the head builder i guess for the sponsor came in, said the noise is due to pipe knocking on the studs. he mentioned that "the builders failed construction 101" and physically moved the pipes away from the studs. the noise went away for a while. it came back--extremely loud, and it's coming from the floor below. in january, another attempt came about--this time, they thought it's because a relay pump somewhere between my floor and the floor below could be the culprit. either way, somehow, they told me it was fixed, and the noise did go away. until 3 weeks later--so it just wasn't fixed. since then, we couldn't get in touch with the sponsor and the "head builder" has been avoiding all kinds of contacts, such as not answering phone and always keeping a full mailbox. and the noise has been going on for pretty much 70% of the time the past month. the board was set up finally in january, and the sponsor has a seat on it. this actually isn't relevant. management has not been too helpful, as they keep saying it's between us and the sponsor and it's not management's job to deal with these things, but when they do reach out to sponsor, and last thursday somebody is supposed to come in. the guy never did--apparently stuck in traffic! and since then, again, nothing. meanwhile, the noise keeps going on and i have had to sleep on the couch, getting very bad sleep. what are the actions i can take here? thanks in advance. [less]