WD TV Hd live freezes

Since a few weeks my WD TV live box behaves strangely. Sometimes it seems to freeze in the file I am running/watching listening to. (the turning round icon keeps on turning for ever) Most of the time I can opererate the menu files but… the audio and sometimes video too of the frozen file keeps on going. Opening and running other files is impossible than! Switching off (sometimes impossible too) via the remote and switching it on again does not help. After starting up things seem to have stayed frozen in the same last state. This occurs in all options(playing audio, video(avi, mpeg4), via network as well as via the attached Harddisk. Even Youtube files via network freeze. I have tried switching back to the standard factory settings several times as well without having a result.   However… Unplugging the power supply(hard reset) unfreezes the player! (it works fine again for a while) Last week it installed the new flash software via the Internet connection. After this I was curious to find out if things have stayed the same.  Unfortunately it was still the same! Once in a while it freezes again. 

What to do?!