Indeed - a "record with reminder" is a facility that V6 offers and could also explain this. There's 2 reasons I suspect it's not the cause here..
1: The OP would get a "Programme blah blah" is due to start shortly" popup 5 minutes previously, they've not mentioned that.
2: A reminder needs to be consciously set up or the default set accordingly - I'd have thought the OP would therefore know.
But all that said... good point. @slartibartfast1 - this is another possibility but check for any onscreen notifications a few minutes before the channel changes.
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