Sagem HDMI will not let me access the recorded shows and freezes the machin?

the machine was working fine and then suddenly it will not let me access recorded shows, screen just goes blank and freezes when i press the list button on the remote. all other functiuons seem to work ok. however after it freezes itrequires a full system shut down, un plugged and turned back on to get it going again. Ive set the code to 0000 and also 0044 as it is a UK set box. I have also tried resetting factory settings... can an yone help me? Thanks, Tony