There are a couple of solutions.
The first and neatest is to use a feature in the HDMI connections called
ARC. If you haven't come across this before, ARC stands for
Audio
Return
Channel. What that means is that the HDMI connection between the sound bar and the TV works as a way to get sound from the TV to the sound bar as well as working the normal way. If you like, it's the digital equivalent of the RCA phono AUX connection.
In order for this to work, the TV you buy must have the ARC feature on one of its HDMI sockets. (Check the specs of whatever TVs you have your eye on.) The sound bar you own already has it. You don't need any special HDMI cables. The same type that works for playing Blu-ray to the TV or via the sound bar will work just fine.
There's a little bit of a set-up to do when you get the new TV. The exact sequence will vary between brands and models, but in essence you're turning on a feature called HDMI Control, and then enabling the ARC feature from there.
With HDMI control enabled, what should happen is that as you turn on either the TV or the sound bar then the other device will wake too. When watching from the TV's internal tuner, or any streaming apps, or the Virgin box, then the sound should route automatically to the sound bar. The TV volume control will work the sound bar instead of the TV speakers.
Waking the Blu-ray player, whether it's connected to the TV itself or directly to the sound bar, should wake the TV and sound bar too, and if they're already on then they should change to the appropriate inputs as well.
Your other option involves a device to take the Optical Audio Out from the TV and convert the signal to stereo RCA phono. The box itself is called a Digital to Analogue Convertor. DAC for short. It's a powered box that reads the digital data light signal via optical and then decodes it and creates an analogue version.
These little devices start at a modest £10 or less. They're all pretty much-of-a-muchness. I suspect that a lot come off the same production line, one day with one product name, and the next day with another. You should certainly be able to find one for under £20 delivered.
Many of the lowest-cost ones come with a power cable that will plug in to one of the new TV's USB sockets. Personally though, I've always gone for the versions that come with a small 3-pin power adapter. Touch wood, in all the installations I have done, none of these has ever gone faulty.
Here's an example with a UK mains adapter.
Using the DAC doesn't involve any set up in the TV menus. The sound quality is going to be fairly close to what you'd get with HDMI, but it doesn't have the convenience features of HDMI Control, so you'll be back to using a separate remote for the sound bar volume unless you've programmed the Virgin remote to do the sound bar.
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