Neither am I. I have no knowledge of what modifications were made to your theme prior it being overwritten with an update.
Your source code indicates valid URL’s to the iTunes download image (badge) but the resizing method (whatever that may be) is failing/invalid.
Good image source:
i2.wp.com/r.mzstatic.com/images/web/linkmaker/badge_itunes-lrg.gif
Failure to load the URL:
i2.wp.com/r.mzstatic.com/images/web/linkmaker/badge_itunes-lrg.gif?resize=500%2C9999
Your server responses indicate that every iTunes Download button image is failing with a 404 because of the invalid parameters being passed in the URL. “?resize=500%2C9999” I honestly have no idea what the cause is.