Hi David,
I had the same problem - my beotime suddenly became silent.
I bought the silver membership, downloaded the repair manual and followed the instructions from Lausvi in this forum.
Although Iยดm repairing things since decades, THIS one was really tricky. The clarity of the repair maual is not always impressive, but finally I managed to disassemble the whole clock. And it seems to be a common problem, that the wire which connects the little speaker breaks due to repeated strain over the years.
Sometimes I was at the verge of giving up and looked for institutions that repair b&o devices. On facebook I found a b&o-store in Basel, Switzerland that wrote, that they repaired a beotime for a customer:
https://www.facebook.com/bangolufsenbasel
This would have been my next solution, but at the moment it seems as I could manage to repair the beotime by myself.
Good luck,
Daniel