How To Fix A Blown Plug Socket

Hi.
I have a single plug socket from which a 8 way extension has been connected for the last 2 years (everything is load checked - with everything on max its 750w total draw.
Yesterday the fuse in the 8 way blew (13a). In trying to work out which device caused the fuse to blow (and going through 4 13a fuses) I decided 4 items can't have all developed faults so plugged one directly into the single socket - that plug fuse blew within 2 seconds but I could also hear a crackle, not sure if from the plug or the device - suspect the plug/socket. Tried the 8 way again with nothing plugged into it, and that fuse blew again instantly.

Have now plugged the 8 way into another socket, replaced all fuses and everything is ok with all the kit so definitely points to the original single socket.

My question therefore is, with nothing plugged into this socket,does it present a risk? Its on a ring,so I can't isolate it from the fuse board without killing other necessary sockets. Normally I'd be straight in there to check the wiring and put a new face plate on but its behind fixed units in a recording studio, and I will need an entire day to get enough access to it not to mention having to disconnect and reconnect about 140 audio cables and dismantle the frame for the mixing desk. However if there is a fire risk from it then I'll schedule a day sooner rather than later. Is it also worth isolating the ring each night from the fuse board?

Just trying to assess risk - googleing "plug socket blews fuse in plug" yields nothing useful
If I were you I would remove the socket and check the tightness of the wiring terminals at the back. Likely as not you will find one or more loose connections and possibly signs of arcing. It is easy enough to do but just turn the power off at the fusebaord before you do it. For the sake of a couple of quid it would be worth replacing the socket, too. It is unlikely to be anything more sinister than this. Its not wise to leave it alone because of the inconvenience of getting access to it, you may get a fire.