We had a flooring company install a new ceramic tile floor in our kitchen, the tiles are about 19 x 19. They installed and within the first few months the grout lines started cracking, and not just hairline fractures, but big chunks of grout. The company came out and regrouted. Within a few months again, we noticed the same big grout cracks as well as the "knocking" noise of a loose tile around several tiles. We had someone from a different company that was working on recaulking our showers and such, and they mentioned that it's likely that the tiles weren't installed properly, and most likely that the mortar may not have been of the right consistency, when those few tiles were installed.
This 2nd company offered to redo the tiles, but suggested that we get some extras because it is likely that some would break during the course of pulling up. Of course these tiles have been discontinued. So it seems like we are down to either re-doing the entire floor with a new tile, or continuing to re-grout the floor, with the same result.
Are there any other ideas? Is there perhaps a caulk or something that could get in there and work better than the grout for these trouble spots?