* The Wii U only supports LPCM 1.0, 2.0 and 5.1
* The Wii U does not support any licensed surround formats: DPII, Dolby Digital, Dolby Digital Plus, Dolby TrueHD, DTS or DTS-HD.
* The Wii U does not have an optical out port.
* Optical out from your TV/Monitor into your receiver/HTiB will not produce 5.1
* For Wii U use, only one AV port on the back is active. If you output HDMI to your TV, the AV Multi Out analogue output will be disabled.
* For Wii Mode use, it does output through both in Wii mode though, so you can have HMDI video and analogue audio.
* It is LPCM 5.1 via HDMI to a supporting receiver or nothing.