This is fault common to both Virgin and Sky viewers, so it looks as though it's the actual station that's at fault, as there was a holding picture from France24 with text about equipment but I was unable to translate it (I took german at school).
There was another post regarding the English speaking version a couple of days ago on these forums, I checked the channel and the sound wasn't working.
I tuned into a different channel, then went back a couple of minutes later and France 24 sound was working again. Not sure if that was a coincidence, or if I was just fortunate to catch it at the right time.
The Service you do for others is the rent you pay for your room here on Earth - Muhammad Ali
We tune in to France 24 (English language) via virgin media every day. There has been no sound at all on this channel for over a week now - we have trIed several times a day. We have tried re-booting etc. As far as we know this is the only channel affected.