The sound problem is a technical issue Alison and depends on what sort of system the site is using and it's compatibility, or otherwise, with yours.
Some of us here use the Carnyx link to LG rather than the link from the RSPB website. I get no sound if I use the RSPB one but Carnyx is fine.
Hope that helps.
Birdies LG DU update.
thx very much Mike .. yes it helped. it confirmed what I thought