Every now and again when I turn off the car, there’s a lot of whirring behind the dash and the lcd clocks goes black instead of the screensaver showing.
When I restart it, everything has reset to 2009 /12 o clock. I even had an alert from the tracker company to say the battery disconnected.
The terminals are on tight and clean. Is this a sign of a failing battery? Hope not as it’s not that old and it’s AGM 2010 MY Vogue SE TDV8 3.6 Stornoway Grey- fully loaded

I may be on the wrong track, but it could be worth checking that all the earthing points are in good order, ie front right wing behind the arch liner, there may be more info on other points in the wiki section.

I think it’s sorted now. I checked the battery connections and they felt tight by hand but when I put a socket on to tighten it, the positive moved. I slackened it off and tapped it down further so the post was proud of the clamp then re-tightened. Seems fine now 2010 MY Vogue SE TDV8 3.6 Stornoway Grey- fully loaded