Washing machine makes loud knocking noise on 1400 spins (transport bolts are out and machine is level) I have 12mm laminate on 5mm foam underlay in the kitchen to which the washing machine sits. The rear of the laminate where it reaches the back wall is somewhat 'bouncy' and i believe this is the cause of the knocking on spin. It's solid where the front feet are, just bouncy and uneven by the back legs. I don't want to take all appliances out, plinths up, and lifting all the flooring just to look at this. What i was thinking best plan is to draw a line where the front feet of the washing machine are, cut out the laminate flooring from that point, lay 18mm osb, and silicone the gap between the laminate and osb. Or perhaps just do this for the back feet and leave the front as they are? Does this sound feasible? if so what is the best way to fix down the osb, and what packers can be used to ensure it's level? If not feasible any other suggestions? Machine is under a worktop, probably another 10mm to play with. I have levelled the machine best i can, but the flooring under the machine is not the same level as outside it, so whilst i have levelled left to right perfect, i can't be sure it is level front to back. Thanks for any help with this, it's a new machine with a 5 year parts and labour warranty so want to make sure flooring is spot on.