I should add that the globes were working before getting back to my place.
GI lamps or feature lamps ?
If they are GI - then I'd be looking at the connectors... I'll bet the IDC connectors are worn and toasty brown !!
Connectors were replaced from memory. Try reseating j120/ J121 on power driver board, sounds like connector may have loosened due to transport. Test globes that appear to be out in a known working socket eg backbox panel before disguarding.