You need to update the firmware to version 1.00.23.
NS, October 2011
See http://redeyedmonster.co.uk/2010/03/30/humax-pvr-9200t-freezing-locking/
RedEyedMonster, October 2011
Not really anywhere near enough information for decent answer (for example WHAT freezes? and under WHAT circumstances?) but I sugest that you start by have your aerial checked.