The Arc technically doesn’t “pair” with the remote….the remote sends a command to the TV, the TV sends any volume commands to the Arc via CEC. 

You want to figure out how to have two remotes connect to your TV, not your Sonos. Usually, that requires them to be the “same”, since almost no electronic devices can recognize two different/diverse  remote signals.

i’m Confused? my apple tv is plugged into my TV ? and so is my Virgin media box? I’m still unsure what to do?

The Apple TV is sending CEC commands to the TV set’s internal computer. The TV’s internal computer processes the signal, and sends it out to the Sonos to react. Sonos isn’t actually connecting to your remote (not the Arc, at least….things are different with older Sonos soundbars)

You need to make both the Apple TV’s remote work at with your TV at the same time as your TV’s remote. Check with the TV’s manufacturer’s manual, or contact their CS with your issue. 

In general, it should “just work”. There’s really nothing you should need to be doing, assuming CEC is turned on on your TV set. The Apple TV’s remote connects to the Apple TV, and sends it’s signal to the TV. The same with your Virgin Remote….it should be communicating with the Virgin box, and sending a CEC signal with volume information to the TV set. Then the TV set processes that data, and then should send it out to your Arc via the HDMI-ARC / CEC command set. 

Note, your Virgin remote should not work when the Virgin box is “off”, much the same as your Apple TV remote shouldn’t work while your Apple TV is “off”. Fortunately, in most cases, “off” really means powered off, they tend to still send signals even when in standby.