rpmdrake errors "reading synthesis file"

Today I launched rpmdrake from command-line and noticed this error message that could be delaying the starting.
Do you know how to fix this? Updating all media didn't help.
- Code: Select all
[root@HBD-1866 NetworkManager]# rpmdrake
Ignore the following Glib::Object::Introspection & Gtk3 warnings
Subroutine Gtk3::main redefined at /usr/lib/perl5/vendor_perl/5.20.1/Gtk3.pm line 296.
Use of uninitialized value $value in numeric eq (==) at /usr/lib/perl5/vendor_perl/5.20.1/Gtk3.pm line 545.
Impossible to set by_group view as default
getting lock on urpmi
examining synthesis file [/var/lib/urpmi/Core Release/synthesis.hdlist.cz]
...
examining synthesis file [/var/lib/urpmi/Tainted Backports/synthesis.hdlist.cz]
problem reading synthesis file of medium "Core 32bit Backports"
problem reading synthesis file of medium "Nonfree 32bit Backports"
problem reading synthesis file of medium "Tainted 32bit Backports"
unlocking urpmi database
Do you know how to fix this? Updating all media didn't help.