VBA chart: scale giving strange months

hi

tried to be concise in the the title not sure if it makes sense!

anyway i'll try again.

i have attached a pic to show more clearly, i am outputting charts from vba and they are giving me a problem with the x-axis scale. all the months are fine except when i get to august - 08 it calls it july - 08.

when i hold the cursor over the data point it correctly says aug - 08 point, but on the axis and display it show july - 08, so 2 july - 08's next to each other. i have messed around with the code for hours to try to get it to change and its driving me mad as i have done so many charts and so much code i cant afford the time to go and start again (even though i know this would probably fix it, damn computers!). anyone seen it before or have any ideas on how to fix this?

any help much appreciated.
thanks

steve