Xbox one Hdmi in , DTS 5.1 ?

Not going to work. The Xbox One currently has zero support for Dolby Digital 5.1/7.1. It only supports Stereo, Uncompressed 5.1/7.1 (which isn't Dolby Digital), and DTS Digital Surround over HDMI. Your headset doesn't accept DTS and optical cannot support
uncompressed 5.1/7.1 (not enough bandwidth).

It's best to wait for Dolby Digital support to be added. It's coming.

5.1 and 7.1 only via hdmi

Dts and stereo via optical

It would not allow you to select 5.1 uncompressed when set to auto because your TV does not support 5.1 uncompressed, which the TV reported during the HDMI handshake (generally, uncompressed 5.1 would require a receiver). Even if your TV did support uncompressed
5.1, that can't be sent over optical anyway--only compressed 5.1 (i.e. Dolby Digital or DTS) can be. The Xbox One does not currently output Dolby Digital. It does apparently output DTS, but your TV won't pass DTS over optical from what I can find (most won't
pass 5.1 at all but looks like yours will do DD). As suggested, you can try running optical directly from your Xbox One to your soundbar with the One set to output DTS.

Titanfall is having this problem, hdmi through my receiver. Tried 5.1, dd, and dts

I've encountered the same issue, e.g. when the rear right speaker is emitting it's test signal I can hear some sound coming from the front right as well (albeit at a reduced volume). I'm using an HDMI matrix that extracts the 5.1 audio and passes it via
optical to my Logitech Z906. I’ve tried to rule out as many issues as possible, but it does seem that Xbox One cannot process 5.1 DTS/DD correctly. I've tried the following tests and all exhibit the same audio issue:

Confirmed that the Xbox One is set to output uncompressed 5.1 bitstream, and I've tried using DTS as well as Dolby Digital.

The HDMI matrix EDID is set to 5.1

The amp confirms that it's decoding a 5.1 DTS or Dolby Digital signal

Tried a different Xbox One (Xbox One S)

Switched HDMI cables with ones known to work in this setup

Switched to using a port on the HDMI matrix known to work in this setup

Connected the Xbox One to the amp directly with optical cables known to work in this setup (thus ruling out the HDMI audio extraction technique used by the matrix box)

Connected the Xbox One to the TV via HDMI and the amp via Optical (thus ruling out the HDMI matrix box completely)

Connected the Xbox One to the TV via an EDID manager set to 5.1 multi-channel audio, and the amp via Optical (thus ruling out any EDID confusion between the Xbox One and TV)

Switched the Logitech Z906 to a Logitech Z680 system I have in my den.

Run the test on something known to work, e.g. PS3, and piped it through the Xbox One’s HDMI passthrough (hdmi passthrough is set to surround sound)