Rattling chain noise - Siemens washing machine

Hello,

We have a Siemens WDI1440. It's 18 years old.

It's making a rattling noise:

mostly when the motor is 'cold' (ie in the first hour or so of running a programme)

only for about the first second of the drum turning (ie. just as it starts turning)

when very cold, it might keep making a faint rattling sound as the drum spins

I've record the sound here. The first second is typical, then I opened the detergent drawer and as it was a cold day you can hear the faint rattling sound continue as the drum spins.

https://recorder.google.com/1f133ba2-7746-488b-87b0-15915aed2703

We had it repaired 5 years ago and the sound stopped for a while, but soon started again. It's getting louder, but it seems to be working OK otherwise.

What could this be, please? I'm wondering if it's worth calling someone to repair it again or whether it's time for a new one.

Thank you very much in advance!