Thanks Dan Gleebles for helping out, it was an earth problem. I have had it looked at by my local rel dealer and it needed some soldering work, but all is well now

.....or so i thought... i was using a marantz sr4200 amp and getting less than what i expected in return from a £500 sub

, whilst using the marantz i was getting some of the range of sound but not all, and not really impressed with the setup.
I took the sub to a friends house and plugged it in to a high end denon amp and was amazed at how cheaky this little bugger was!! it had a good go at all signals thrown at it

and even tried to remove the door from it's hinges!!
the owner of the amp has a servo 15, and this put me to shame quite a bit as this was more interested in taking my shoes off and empyting my pockets of loose change than geting me involved in a film (absolute animal)(but damn fine fun!). (turn it down gary it's not a weapon!

!!!)
many thanks as it no longer humms and i am happy
cheers