Check if the issue has been reported (bug report) on Mandriva's
Bugzilla. If it has not, make a bug report. If it has been reported, add any information you can. Reporting issues such as what you experience is the best way to make sure Mandriva works as expected for you. Mandriva wants their distribution to be as near perfect as possible, but the only way that can happen is if the user community provide useful feedback when things do not work correctly.
HTH,