I have had the same problem and am now on my 5 lg combi in just over one year. as it is now out of warrenty I have done some investigation. It would appear to be a software problem. I have changed drives to no avail. there are several hidden menus which settings can be altered on but no-one will give me the correct settings. LG will answer my e-mails but just say take it to a repairer. I have chatted to a couple on the off. all point to corrupted software but as of yet I have not been able to source any to reload. I have been at it for a couple of months and would honestly say take it for repair, although as I have had so many fail I feel its time for me to change manufacturers
John Waller, February 2007