Sgt_Kickaxe - 2:48 am on May 1, 2012 (gmt 0)
On top of that the affiliate links are setup as a 302 redirect
302 is the default browser behavior so it's not likely to have contributed to your rank reduction. The ranking effect of exact match domains is the more likely cause, especially if you do not have a brand name that matches the keywords used. Generic or product based exact matches have been widely reported as having less influence.
e.g. blue-widgets-under-the-moon-at-midnight dot com is not a brand and so it's likely considered over optimization for those keywords.