Hostel Pangea - Don't go there. rude staff and impossible to sleep

There was no chance to sleep in this hostel, because of a rockband above our heads. And the (cocaine using) staff didn't take any reponsibility or provide any service and was really rude to us. Although we paid 30 dollars we got a small shitty room at the back of the hostel with a rack in the ceiling above our heads. Then a rockband started playing above our heads at 9pm. and it didn't stop all night long (we had a plane to catch the next morning at 5 am). When the rockband was still playing at 11pm, I went to the reception. They told us that it was not their responsibility because the band was outside the hostel. When we asked them for another room they told us they were full. Then me and my boyfriend got went to the reception again at 2 'o clock in the night when the rockband was still playing. We went to the reception again. They yelled at us that it was not their problem. Then three other people from the rooms that were beside ours came complaining too (They had complained earlier in the evening too). All of a sudden 4 rooms at another part of the hostel were empty.... So at least we slept one hour for 30 bugs...I think this happens every night and they rent the 'rockbandrooms' during the day (when there's not yet a rockband playing). And people that arrive at the hostel at night get other rooms (because otherwise they would hear the rockband and wouldn't take the room). We didn't get our money back either because they don't do refunds. So they let us pay 30 dollars to hear the worst rockband of costa rica banging on our heads all night long.