Ours sounds more like a bag of spanners being shaken!
I’m sure I googled it at the time we bought ours, expecting an imminent gearbox rebuild, and found it to be very common / normal. I think there was a revision in 2016 that improved the layshaft bearings.
We have a couple of young peoples cars in the household - the Up and a Citroën C2 and the Up feels very refined for a small / budget car by comparison.