Problem with Vibo slide-out half-circle carousel

We recently had a completely new kitchen designed, supplied and fitted by one of the UK’s largest kitchen manufacturers. This included the Vibo slide out half circle carousel listed as KCME660/60FBC on the assembly instructions left behind by the fitter
The storage baskets have been in use for three to four months. The maximum load per basket on the instructions is 9 kg for the 660 and 11 kg for the 760. During that time, our maximum load has never exceeded 5.5 kg on the top and 3.5 kg on the bottom. Initially I was able to lay three pizza pans flat and still rotate the bottom basket out. It dipped gradually so that one by one, I have had to remove the pans. In the past two weeks it has actually begun scraping on the base of the storage unit when rotated. It is obvious that there is quite a lot of vertical give in both baskets. The lower basket appears to have dropped by at least 17 mm or slightly more.
I have made the company aware of the situation and do not anticipate a problem with them honouring their obligation to put things right. However, since this is only the latest in a series of post-installation problems, which have mostly been attributable to the standard of work during installation, I have learnt to seek an independent opinion before entering into a discussion with the kitchen manufacturer. Since the maximum load limit has been respected, I can only assume that this is an installation-related problem, and possibly/hopefully just a case of doing some required tightening. The local showroom rep is actually coming today, Wednesday 3 December to drop off parts for another installation repair and I would be very grateful for any information before then. Has anyone out there had problems or can they suggest a cause and a way to resolve the problem?
Thanks in advance for your much-appreciated assistance.

 

Hi, and thanks for answering me. The easiest way to show you is to direct you to this link:
http://www.hafele.co.uk/shop/p/slid...circle-carousel-645-790-mm-spindle/53235/5720

The kitchen maufacturer is Sigma3, head office in Wales but operating for the last x number of years in the Southeast where we live as "County Kitchens by Sigma3". I have established that the Vibo pull-out carousel was supplied to them by Häfele. When I spoke to a member of the Häfele technical team, he was very nice but unwillling to advise me directly as our contract is with the kitchen manufacturer and any queries to them must be channelled through Sigma3. He did offer to speak to their fitter on the phone when he came to the house but that didn't seem necessary. However, after the new fitter came last week, I discovered that in tightening the drooping trays, he had left the lower one jammed and no longer able to be pulled out! I have notified the kitchen people as the fitter is coming back on Monday 16.12 to correct other issues dating from the original installation. With use, I can now see that both trays need to be raised as there is wasted space at the top of the cupboard that could provide room below to lay things flat. Thanks in advance.