Tuner loses settings

Hi, I tried a few searches on this but found no information.

My tuner on my 5001 loses its settings once I go into standby mode. This fault has only recently developed. I rarely use the inbuilt tuner so its not a major issue (prefer to use VCR). Occasionally though I want to record something on VCR at same time as recording on 5001.

Has anybody else experienced this fault - I hope it’s not an imminent sign of a more “catastrophic” failure?

It is still under guarantee just I think (assuming I can find the receipt). I have a hacked version of 098. Woulkd this invalidtae the guarantee - or would I be better to re-install the official version if I decided to claim on guarantee?