Hi Dynamo700
Each 360 remote pairs 1 to 1 with the box, it does not use infra-red (IR). This means you can only use one remote with a box and not multiple.
You can use some third party remotes such as the OneForAll URC7125 - use the SimpleSet setup process and choose Ziggo manufacturer.
There's also the OneForAll1240 - if you enter code 1582, It's not as expensive as the 7125 and has 4 selects for tv/sat/amp/dvd. I have this one. It needs direct line of sight to set it up.
Also the Logitech Harmony remote works. You need to set them up as a "Ziggo Mediabox Next"
Some TV's smart remotes also work with the 360 box. I have an LG and can set it up to control my 360.
Some TV's recognise the box as Virgin, with others you may need to search for Ziggo, or Ziggo Mediabox Next.
You can also control the 360 by using the Virgin TV Go app.