Hello, What kind of noise? If it is a type of gurgling and the waste water drains slowly, I would suggest you invest in a good old-fashioned sink plunger i.e. a rubber cup on a stick similar to what Dalek's had (if you're old enough to remember!). Apply the cup to the shower drain and plunge up and down - trying to get a good seal between the rubber cup and the drain edge. This will result in all sorts of particles being dislodged and sucked up back into the shower tray. I don't want to describe this in any great detail but it will not be too unpleasant. Do the same with the sink drain but you'll need to block the overflow hole for any plunging to be effective - a second pair of hands is useful to press a wet flannel into the overflow hole. Again, this should dislodge any debris resident in the trap below the drain. If non of the above helps try a product called "Drain Magic" or similar from a good hardware store. It's a strong acid that eats just about anything lurking in your drain. Follow the safety instructions exactly! What could be the cause? Generally - hair, body grease, soap, detergent fat and any other bits that wash off the body. Hope this helps, Andy