Why has BBC iPlayer has stopped working on my Mac?

iPlayer has stopped working on both myiMac, running El Capitan version 10.11.6, and my MacBook running High Sierra. Both versions, and Safari, are up to date. The symptoms are; iPlayer loads but when I click on the play icon to play a programme, I just get a whirring symbol, and the programme will not launch. It started doing this very recently and suddenly.

The only change I have made recently is to upgrade the MacBook to High Sierra. I cannot upgrade the iMac because it is too old.

Anyone else had the same problem and found a solution?

Regards