I started to have tiles in my kitchen, then in my sunroom and will soon have my bathroom with tiles. Like trulyblessedmum, I could not for a while have the tiles completely clean, no matter how many times I rinsed the mop. They were not shining as they should, and yes, if you walked on them wearing socks, the socks would get dirty. But then I started to use Oxy Clean, a very versatile stain cleaner product (it is great to get stains off your clothes, even blood stains). I dissolve one and half or two measurefuls in four litres of hot water, wet the floor with it with a mop and leave it to work for 10 minutes. I then mop up the liquid (don't even need to scrub) and dry the floor with an old terry towel. The floor sparkles and any stains on the tiles or the grout are gone. The grout looks darker but reverts to its original colour when completely dry. Suzanne

What product(s) are you using when you scrub? It could be that the grout has simply faded into that white, cloudy color, and maybe you have to re-stain the grout. I use the StoneTech products when I need to seriously clean my tile and grout. I learned about them from the guys at the John Bridge tile forum. If you don't get a solution to your problem here, go to that site and do some reading on the Cleaning, Restoration and Sealing forum. Here is a link that might be useful: John Bridge Tile Forums

The best way to reduce grout maintenance in a shower is to use the right grout in the installation. The old cement-based grouts were hard to keep clean. Many seemed to grow mildew like it was a cash crop. The newer urethane grouts are essentially a durable plastic, non-porous, and do not provide hiding places for mildew. We use nothing but in our bathrooms on floors, walls and shower surrounds. It's more expensive than cement grout, but considering the overall cost of a tile job, the different is minimal. Quartzlock was the original urethane product. It has now been bought out by Bostik. It is definitely a pro product, not recommended for any but the most experienced DIYers.

2 cups hot water + 1/4 cup OxyClean Powder. Soak grout with this solution for 30 minutes (keep wet) then use grout brush to clean. Amazing how well this works. I bought a "grout cleaning brush" and "long handle" from janitorial place that works great and easier on your back than crawling around on your knees. This will clean the tile & grout. May need to repeat.