Problem with speakers?

hey guys need a bit of help. i was using these advent speakers (http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=160598931011#ht_1138wt_1139) (not off ebay bought them from PC world brand new just want to show you which ones i am talking about) only had them since november and we had a party at the weekend and they all of a sudden just cut off. the main bass unit, that doesnt even power up. i have changed the fuse and still nothing. is there anything i can do? thanks in advanced