I have a different solution to an IR repeater but it won't be acceptable for everyone.
I use a 2.4ghz wireless mini keyboard similarly to this one
Unfortunately they all seem to come with a power time out and need a key press to wake up after 1 to 3 minutes.
It takes a bit of getting used to but works fine without needing full line of sight.
The box has to be switched on manually, unless its recording, about to be recording. in active standby or has only been switched to standby in the last few minutes.
Which keys do what are provided on the youview site:
Additionally to what it states there the 'I' key is also an 'Info' key.
On the plus side it is easier to enter searches, plus the F4 key takes you directly to the recording list.
It's not immediately obvious from the youview keyboard mapping PDFs is that the 'Del' key has been mapped to the back function, and the 'Back' key to the delete function.
Sent from chimpingtongb's attic (or possibly not).