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This is utterly ridiculous. The laptop is now useless for the thing I use it for.
Tried going through VLC help (it's not the only player I've tried) and none of it's suggestions changed anything. (And there is no maximise performance power plan to change to.) Does anyone have any suggestions on how to sort this ?
I'm going to go try the DVD on the study PC now, to see if that has the same issue. I've already tried DVDs I've played on the laptop previously without issue, in order to check, and they now have the same problem. (I accept it may be coincidence rather than the update, but something has changed at that time.)