Thanks for the replies, have checked that it's level it, it only has two front adjusting supports and I have put both the same, I've pulled it back out of it's space into the kitchen space and it's still continuing a couple of hours later, thought the space might have been too tight although it's in line with whats in the manual.
The manual does make reference to a number of humming noises etc. and them being normal which is a bit worrying, will call where I bought it tomorrow to get them to have someone to look at it cos I couldn't listen to it constantly.