Africa needs help again! Room in room?

Hi guys I posted some time ago questions about building materials. So far i have acces to gypboards max 0.5" and whole drywall supply (not bad for Africa lol) Now some questions. I have a square room 16,5ft x 10ft with 8,3 celling (I know, very small..). The walls are allready covered with fibreglass and celling is gypboard 0.25" on wooden truses . We cant get rid of deep rumble (is very soft but you can still hear it :( ). So we decided to built room in room. Could you guys give me some design ideas. The floor is stones on fine desert sand so i hope i dont have to put floating one on that. Would another angled, suspended celling help getting rid of the noise? Thank you for help in advance Greets Drakem P.S My english id getting better, but still crap.. :D

Hi Drakem - where is the rumble coming from? Are you close to a highway or is there a rhino stampede heading in your direction :):) cheers JOhn

:D :D Ha ha John, thank you for reply It isnt that bad. Yes Im close to main road. And the problem is i cant really locate the noise. It seems to come from everywhere but mostly from the roof. Roof in Africa is very simple just wood and metal sheet, not even proper sealed so you can look outside from your TV room :)) I´m kidding... The roof doesnt have proper insulation. Maybe I should open it first and try to put inside some rockwool? Or just spend the money on proper suspended celling? I´d like to build angled walls. What is the best angle in my case? I have another question. Since here the max thickness of gypboard here is 0.5" is it enough to put double layer and a layer of plywood? Thank You Greets Drakem

Drakem - what are the walls built out of - you say there is fibreglass on the walls - this is over what?? Also what do you do in this room ?? ;) cheers John

Ok. The walls are of bricks, double layer. Early the room was a garage, so its build very simple. All windows are closed with plywood and gypboard and sealed airtight . Fibreglass ( they call it here Isotherm, is sort of white,fluffy thing) is just nailed to. It should be a tracking room if it ever happens :( . Greets Drakem P.s I´ll try to make a drawing of the room and post it here.

This is a drawing of my room!