MySQL xtrabackup issues on MyISAM tables.

Hi,

I have recently set up a backup strategy for our database using innobackupex where we have the majority of MyISAM tables, we take a backup of the tables then prepare the backup and move to an offsite server. Our problem is when ever we then attempt to use this backup some of the MyISAM tables (not all) are corrupt they are corrupt with the following error “incorrect infomation in file /schema/table.frm” any idea what could be causing this issue and how we can avoid table corruptions?

Thanks, Alex.