Unfortunately, not everything on Netflix is supported in 5.1 and Chromecast (video) only supports stereo as far as we know. The best thing to do is to contact Netflix or Google Chromecast Support.

Yes, there are various Bluetooth adapters that can simply be connected via an aux cable. I recommend one with AptX to avoid any loss of sound quality.

No, that's nonsense...

It is possible to combine these products. However, there is also a wireless version of this subwoofer: Klipsch R-12SWi - Wireless Front Firing (400W, Subwoofer, Black Poly Veneer)

You can either connect it to your TV with HDMI output to the sound bar, or connect it to the sound bar with output to the TV, as shown on page 4 of the product manual (available on our website).