@Anonymous User Try replacing the batteries in case the ones given were faulty. 🙂
@Anonymous User The remote itself could be faulty. Does the light on the box flicker when you press the buttons?
Did you buy it from the sky accessories website? You may want to contact sky over it if you bought it from them. 🙂
@Anonymous User I just remembered, if you have a smart phone, you can download the roku remote app. (Apple/Google Play). 🙂
Also, you can check if live chat can help you.
Click "contact us" at the bottom of the link and select 'live chat".
Best on a PC/Mac. 🙂
@Anonymous User Hello 🙂
Have a read of this help page.
Sounds to me there is possibly a IR receiver fault or some other inherited fault on your white box.
Personally if it was me, i would send the remote controller back to Sky Accessories Store (assuming you purchased it from there) and request a full refund.
Where if i had a TV with a HDMI port, if would pick up the newer nowtv black box with one of the bundled passes which places like Argos, Currys and Sainsburys are selling off cheap at the moment.