Ir extender and humax pvr9200t

I recently bought a powermid dual power to use with my Humax pvr9200T.

The powermid receiver and emitter are separated by a wall and I'm
pretty sure the signal is getting through with no issue.
The problem is that in order to use the remote via the powermid system
I have to press each command twice.

Therefore if I want to get info, I have to press the I button twice
within a second or so.
If I want channel up or down I have to press the button twice quickly
this moves it one channel, I'd I continue to press the channel button
it continues to change the channel, if I stop then I have to press the
button twice again in order to get started.

The remote works correctly (ie with one push) when used directly with
the humax.

Obviously this is somewhat annoying, can anyone possibly suggest what I
can do to make the system work as intended?

Many thanks

David