Hello, I’m Nathan, and I’ll be assisting you today. My livelihood depends on your positive feedback, so your satisfaction is my highest priority.
Sorry to hear you’re having trouble.
1581 (or 11581) is the only IR codeset for Niko tvs.
It is possible, however, that no matter what code is used, your remote will not be able to control the devices you wish to use it with. Cable/satellite/AV Component manufacturers include basic functionality for common devices at the time the remote is made, but are not able to provide coverage for every make and model, and are not able to update for every new device that comes out, so there is no guarantee of compatibility. ATT remotes are known for poor compatibility with all but the most common brands/models, so chances of it working with an "off brand" tv like the niko are very low. In short, if that code doesn't work, then the att remote is not capable of working with your tv.
Your best option may be to purchase a more robust, true universal remote to control all of your devices, such as a logitech harmony (click here for example) that will work for all of your devices. It is programmed through an easy to use software program on your computer, which downloads the most up to date remote and device codes from the internet, so it is virtually guaranteed to work with all equipment. It will also give you easy to use macro functionality, so you can press a single button to watch a movie for example, and it will turn on the dvd player, tv, and surround system, tune to the correct inputs on the tv, and start the movie playing, etc. Because of the online database with specific codes for each model, this type of remote has much greater functionality than the basic universal remotes (including the one that came with your system.)
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