Mick!
Ive been following this with the hope to actually participate something, now i can.
I dont have my silver vision box but i can confirm this works with the black box.
*** YOU WILL NEED A BB CONNECTION ***
my black box has sat in the loft for almost two years, so its missed a few updates, but after being off work cos of the christmas hols, and that Bt have rolled out the ''new look vision'' linux software. I figured id try and download the latest firmware.
this works on any BB connection not just Bt.
***this will only get you the new firmware not activate your box ***
Do not plug in your ethernet cable just yet
press and hold ''ok and down''
insert power lead whilst still holding ''ok and down''
wait for the cog to come up on screen.
plug in the ethernet cable.
You should see the progress bar start to fill up once download completes
2 cogs will come up on screen and again a progress bar fills up.
once completed you will see the ''new look vision logo''
let it look for your hub, or let it come up C03 error, then go to diagnostics info, and there it is. The latest software installed on the box.
I have no knowledge of linux, but i figured this may help you.