Odd Problem in modern grand prix series I need help please

after putting some 80 plus hours into this and just after the release of the Road America track (not saying its the cause of the issue just a time stamp of when it occurred) I have had a problem in the modern grand prix series. Basically despite saying on the menu screen that I am on race 10/10 after finishing the last race of the series at Catalunya it says I’ve only done 9/10 the loading screen tells me I’m leaving Road Atlanta and going to Catalunya again, over and over again in fact. As things stand at the moment I have driven this race at least 10 times. I have factory reset the console I have done the race off line and deleted my local save all without resolving the issue does anyone have any ideas to save my sanity and my rapidly balding head

http://forums.forza.net/turn10_postsm49772_Road-America---Problems-with-update-while-in-the-middle-of-a-series.aspx#post_49772