That's because something is blocking it, when you enter stereo mode, the service runs a license check, some VPN's and security software block it.
When they block it, the service see this as an interruption, and potentially an attempt to hack, other reasons, and turns off.
I have only known this to happen due to VPN's blocking the online license system.
Issues on headsets with DTS support? – Support (steelseries.com)
hearthstone - NordVPN adapter (NordLynx Tunnel)
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Also note you cannot buy a license for Ultra, only for Sound Unbound. Which I suggest you do, the newer versions are better.
Owning a Sound Unbound license generally entitles you to use Ultra, as its a part of your license (in the app).
Not only do you get new features, but DTS also made the APO and technology, not me.
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MediaFire is a simple to use free service that lets you put all your photos, documents, music, and video in a single place so you can access them anywhere and share them everywhere.
www.mediafire.com
My friends AMD was not listed, with an edit the driver installs and works perfectly.
Also, encoded formats went from none, to all supported by the TV.
He now has multichannel Interactive:X on his TV.
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AMD DCH - DTS Edition - YouTube (Screen recorder, downmixes to 2 channel).
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Virtual Audio Cable 4
Can be used to trigger speaker detection (the speaker pin setting, right side of the control panel), or keep Interactive:X always on.
If you want to use the .reg files on VAC, open FX, press properties, to open an advanced regedit, then file import.
Run the panel as admin, disable the devices to change settings.