Works for me without problems. I used the syntax:
How old is your last change in media? I found this remark on the Changes plugin page:
Filtering by age is possible, too. Just specify the maximum age in seconds. However, please note that this plugin can not display changes older than recent_days.
In my wiki recent_days
is 7. So I won't see any media changes if all media changes are older than 7 days.