Matched library in a mess in cloud only?

Hi

I Have 500 odd albums all tagged perfectly and up until recently all showed up as I wanted in itunes match, starting last week, it has become a total mess on IOS only. I have a windows 8 laptop where the library is physically stored, all shows up perfectly on itunes here, like wise all is fine on my work pc (windows 7) using the match service. Just to confirm its not the tags because the same library also serves a sonos system at home which is also fine. problem is on any IOS thingy, Iphone 5, ipad and ATV the library has become a random mess particularly under the artist tags, my 500 odd albums are now over 800 and some artists are gone altogether whilst others have been added (of whom I own nothing!).

Just to reitterate, up till a week ago it all worked fine - I haven't added to the library or anything in that time either

I have tried deleting the matched library completely out of the cloud, off the computer then reinstalling it and rematching, problems seems to get worse everytime, the matched library on IOS is now fairly unusable - any ideas would be welcomed

Bill