I assume you mean "pre-wired" for speakers...
The image looks like the blue wire would be a 4-conductor speaker cable that will head back to some central location. The two yellow wires would then be 2-conductor cables that go to the L/R speaker locations (where are those on the outside). That plate is then replaced with a volume control. By the sunlight, it appears that this is an exposed location? You'll need to cover the control with an outdoor box (or control volume remotely and have nothing here).
Where do those blue wires end up? Hopefully where your receiver is?
Your receiver has a "Zone 2" output. Connect the variable output to an external amp and speaker selector (with impedance matching if you're doing more than 2 zones) is the cheapest solution. Amp to a remote control-capable selector with individual zone volume, such as the Aton DLA series, would be the next step up.
I assume you really only have 2 other rooms wired (master and patio), and the media room is a 5.1 pre-wire, with all the speaker cables coming to one place?